Questions related with (base 2) representation of numbers and their unique properties arising out of number representation.

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105 views

XOR of Three Integers

How would you prove the following: Given three non-negative integers $a, b, c$; if $a \oplus b \oplus c = 0$ then $(a - k) \oplus (b - k) \oplus (c - k) > 0$ for any $0 < k \leq min(a, b, c)$ ? ...
4
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1answer
432 views

Finding the binary representation of the $n$th Fibonacci term

Objective: To find the binary representation ( or no. of 1's in binary representation) of nth term in Fibonacci sequence where n is of the order 10^6. My current approach: Find nth term (in decimal) ...
3
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1answer
175 views

Fast fourier transforms of random binary data

I am a physicist who is trying to make sense of FFTs and binary data. Say I have a series of random binary data, which is measured with a repetition rate of 400Hz (interval time of 0.0025s). I have a ...
2
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1answer
22 views

Express a binary operation in decimal

Is there a way to represent binary operation in decimal. What I mean with this is for example a set of decimal operators that would give the same result as a x>>n a ror(x), etc. So far the only thing ...
2
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1answer
73 views

Count 1-bit in binary integers

Given an integer range [A,B], (1) What’s the probability to get a 1-bit if we first randomly choose a number x in the range and then randomly choose a bit from x? (2) What’s the expected number of ...
2
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1answer
41 views

Computation and Elimination (Solution Verification)

Consider a set B (of binary strings) given by the introduction rules: \begin{equation} \frac{}{\epsilon :B} \quad \frac{a:B}{s_{0}(a):B} \quad \frac{a:B}{s_{1}(a):B}\end{equation} ...
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1answer
22 views

Does decimal fraction has hex value?/can hex be fraction?

I was wondering if a decimal fraction could be converted into a hexadecimal fraction? I have seen it many times ? but I have been also told that decimal or binary fraction has no meaning in hex. ...
1
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1answer
31 views

How many binary string are there such that there are no k consecutive characters are the same?

Given number $n$ and $k$. Count the number of string with length $n$ such that there are no $k$ consecutive characters are the same. Example with $n = 3, k = 3$, the answer is $6$. ($110, 001, 101, ...
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92 views

Number of 'unique' one bit binary functions with N-bit inputs

Consider the set of binary functions that takes an N-bit input -> 1 bit output. There are 2^(2^N) elements in this set. Now potentially reduce this set by restricting to only considering functions ...
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216 views

An Upper Bound for an $[n,k,d]$ Linear Binary Code.

I've been reading about the various upper bounds for different types of codes. Recently, I came across a statement that is similar to the Singleton Upper Bound that I am having trouble proving. The ...
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683 views

Binary representation of powers of 3

We write a power of 3 in bits in binary representation as follows. For example $3=(11)$, $3^2=(1001)$ which means that we let the $k$-th bit from the right be $1$ if the binary representation of this ...
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47 views

Upper limit for adding N numbers in grid of N processors in parallel

We must show how N binary numbers, each consisting of N bits each, can be added in a linear grid of N+logN processors. Suppose that the binary digits can be inserted directly in each processor of the ...
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203 views

Unambiguous expression for binary strings containing some substring

Is there some systematic way for finding an unambiguous expression for a binary string which contains a certain substring? For finding expressions not containing a substring, it is sometimes easy to ...
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0answers
81 views

Why is $2^{16} = 65536$ the only power of $2$ less than $2^{31000}$ that doesn't contain the digits $1$, $2$, $4$ or $8$ in its decimal representation

$65536$ is the only power of $2$ less than $2^{31000}$ that does not contain the digits $1$, $2$, $4$ or $8$ in its decimal representation. http://en.wikipedia.org/wiki/65536_%28number%29
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29 views

Leibniz Binary Representation of Squares

Leibniz claims to have found patterns in the square numbers and their binary representations. I cannot see any patterns at all. Here are the first ten squares and their binary representations, can ...
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0answers
47 views

Recurrence relation for Binary String Question

I have a question which has been a little stumped. I'm pretty sure I know the answer, but don't know how to prove it to be true. Here it is: "Given an infinite length random binary string, what is ...
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0answers
38 views

Is there a way to get the n-th of bits of 2^k

I have a large number N=O(2^k). For simplicity, let's say that N=n^k. However, I only need the n-th bits of N, say for example the 10-th to 16-th bit of N... without calculating the full expansion... ...
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38 views

Why is this number the smallest positive normalised binary value?

In the AQA A2 Computing textbook (Bond and Langfield, 2009), they say that this number is the smallest positive normalised value, given a 10 bit mantissa and a 6 bit exponent: ...
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79 views

Why doesn't this base 10 number x mod 2^y work for converting base 10 to binary

Okay I tried to convert 1 million to binary by dividing by a power of 2 and taking the remainder and dividing that by a power of 2 and so on and I got this: 1111010000100100000 Google says 1 million ...
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87 views

conversion of number from base 10 to base 16

I have trouble finding an example of a conversion of a number from base 10 to base 16, where there is a loss of significant digits when using the Euclidean algorithm due to division by large numbers, ...
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1k views

Calculating minimum hamming distance of a code

We use hamming code of (7,4,3); Given 4 bits of information, we'll add 3 bits of parity, and one more parity bit for the 7-bits code. Given $x_3,x_5,x_6,x_7$ $x_1 = (x_3+x_5+x_7) \mod 2$ $x_2 = ...
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29 views

How to show that the spectral radius of a binary tree approaches exp(1) as the N tends to infinity?

How can I prove mathematically that the spectral radius of a binary tree approaches e as the number of nodes tends to infinity? I mean it is true that the increase in nodes number is exponential but ...
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64 views

Probability of getting a Column full rank binary matrix

Suppose I have a $m \times n$ ($m>>n$) zero matrix (all of the elements are $0$). I want to flip $k$ ($k \ge n$ and can be controlled by the user) elements of the matrix randomly. After this ...
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201 views

Recurrent relation for number of ways to get a balanced n-binary tree

In answering a question related to binary trees, I came up with the following recurrent relation: Base cases: $$ f \left (1 \right ) = 1 $$ $$ f \left (2 \right ) = 2 $$ Recurrent relations: $$ f(n) ...
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155 views

Finding the maximum XOR metric

I'm trying to find a way to find n keys (x bits) where the XOR distance metric between them would be greatest. By XOR distance metric I just mean the value when two keys are XORed together. So for ...
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34 views

Predict binary occupancy vector from history of vectors

I have a set of binary vectors where each vector represents one day of occupancy in a house and consists of 48 elements (each element for 30 minutes of the day). Each element can be 1 meaning that ...
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0answers
98 views

Fixed decimal point numbers binary representation

I saw this formula that I cannot understand how it applies (the proof). Q: say we have a $N$ bit register (imagine a binary number with $N$ digits) for representing fixed decimal point numbers. In ...
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48 views

System of equations with binary variables

Is there any way to simplify solving system of equations, assuming that all variables are binary? All equations, however, are seen as equations with real (or, to make things simple, integer) ...
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88 views

interpret reduced cost of all binary variables

I have prepared and run a Linear Programming model in SAS. I have some questions about the output that I can’t find answers to, and am hoping that someone can help. My model contains the decision ...
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140 views

1s surpassing 0s in binary strings of odd length

Let $A(k)$ be the number of distinct binary strings of length $2k+1,$ for which the number of $1$s surpasses the number of $0$s for the first time at digit number $2k +1$, i.e., in the final digit in ...
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168 views

Recurrence relation for the digits of the integer square root in binary

I was investigating a question on the Electrical Engineering Stack Exchange site, available here: ...
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12 views

Estimating how many searches will be needed to justify time spent on presorting an array.

Problem Estimate how many searches will be needed to justify time spent on presorting an array of $10^3$ elements if sorting is done by merge sort and searching is done by binary search. (You may ...
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38 views

Proof by Induction for Splay Tree?

I'm preparing for an exam about Trees. One of the questions that appear in Mark Allen Weiss' "Data Structures and Algorithms Analysis in C++" is: Prove by induction that if all nodes in a splay tree ...
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21 views

Converting From Different Number Systems

I've been taught to convert from base 2 to base 10 using the following process: 10110 = $0\times1 + 1\times2 + 1\times4 + 0\times8 + 1\times16 = 0\times2^0 + 1\times2^1 + 1\times2^2 + 0\times2^3 + ...
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11 views

Redundant Binary Representation

Is it possible to have a technique using Redundant Binary Representation so that repeated addition can be obtained with no carry propagation time?
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60 views

Proving that number of codes with even weight is the same as number of codes with odd weight for a specific code book

Consider the $[n,n]$ code-book $C_0=\{0,1\}^n$ with $n$ being odd and the codes $c_i \in C_0=[c_1,c_2,...,c_{2^n}]$ being sorted in the ascending order of hamming weight (from $0$ to $n$). Now let's ...
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15 views

similarities between two binary matrices

I want to measure the similarities between two matrices A and B. Both A and B contains the feature vectors of sounds and are in binary format. i want to see what is the similarities between these two ...
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38 views

Concrete math generalized josephus recursion understanding 1.15

I am studying through the josephus problem in concrete math , Here is the equation of binary form $$f(1) = α ;$$ $$f(2n + j) = 2f(n) + β_j ,$$ $$\text{ for } j = 0, 1 \text{ and } n \geq 1$$ this ...
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30 views

Efficient way to compute the binomial using $(2^k+1)^{k+1}$

The following web page: "http://introcs.cs.princeton.edu/java/78crypto/" (at Exercise 28) effectively says that: "Pascal's triangle. One way to compute the $n$-th row of Pascal's triangle (for $n ...
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33 views

Binary division algorithm

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how to write a lattice $[\alpha,\beta ]$ in the form [$a,b+c\omega _7$]

$\fbox{1}$ if we write [$2-\sqrt{7},5+3\sqrt{7}$] in the form [ $a,b+c\omega _7$],what is the value of $a,b,c$ $\omega=\sqrt{7}$,since $ 7\equiv 3\mod 4$ $N(2-\sqrt{7})=4-7=-3$ $N( ...
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68 views

What is the result of the calculation: $8.375 - 0.375-0.875$?

Given the base $\beta=2$ (binary) and $t=4$ digits to represent the number in computer with hidden bit representation and symmetric rounding, what is the result of the calculation in floating point ...
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44 views

Biased form with hidden bit

A computer stores a number of 16 bits word using floating-point arrangement. Given that the first bit is reserved for the sign and followed by 6 bits for the exponent using biased form. The remaining ...
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32 views

Search L leaves smaller than node N

So in my binary $kd$-tree I have a node $N$. Now I search for the number of leafs $L$ "on the left" side of $N$ (this includes the left child branch of $N$ and all parents where the node is a right ...
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62 views

What is the number theory behind this?

I am given $3^{1000}$ and asked to find, in base $2$, now many digits it takes to represent this number. According to Wolfram, it is $1585$, but I don't know why. I understand that $2^n$ would be ...
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238 views

Prove that $gx^2 \sim f$

Let $f(x,y) = ax^2 + bxy + cy^2$ be a positive semidefinite quadratic form with determinant $= 0$. Let $\operatorname{gcd}(a,b,c) = g$. Show that $gx^2 \sim f$. I'm not sure how to do this. All I ...
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40 views

Probability, linear independence and study of variant of Lights Out

Using Arduino, some leds and pushbuttons I've created a simple variant of the mathematically popular game "Lights Out". In my variant, the starting configuration is always all lights on; what changes ...
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31 views

Transformation of binary data

I have a function that I try to optimize using Particle Swarm Optimization. Objective function gets a binary string. So these binary strings are candidate solutions of the subject function. I can ...
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50 views

Binary String as number

For 1 ≤ i ≤ n− m, m < n, Interpreting the strings as binary numbers, we have that A[(i+ 1) ..(i+ m)] = 2 A[i..(i+ m− 1)] − (2^m−1)A[i]+ A[i+ m]. Can someone ...
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144 views

Maximum number of truths in an optimized truth table.

I have a math-related question: I have a set of predicates that need to be evaluated. These predicates can have two kinds of operators; AND/OR. When such an expression is constructed my code builds ...