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2
votes
1answer
13 views

Using primes to create unique character mappings for scrambled substring searching

Problem: given a string needle, and a string haystack determine if there is there an anagram of needle present as a substring of haystack? (Assume case doesn't matter). One solution is to map the ...
9
votes
0answers
496 views

Are there “mental calculator” persons that can recognize closed-form expressions?

There are people, sometimes called mental calculators, who is capable of performing fast calculations in their head, involving multiplication, factorization, finding logarithms and roots of a high ...
0
votes
0answers
7 views

Computing Object Classification with bayesian statistics

Say I want to know if there is a zebra $\theta$, in an image $x$. According to Bayes statistics applies to image recognition, I should be computing: ...
0
votes
1answer
34 views

How to complete a table of probabilities ?

Im baffling myself as to why I cannot understand where it came from. Someone please explain to me like I'm five. $$\begin{array}{c|c} x & p(x) \\ \hline 0 & 0.73 \\ 1 & ? \\ 2 & 0.06 ...
0
votes
2answers
23 views

Evaluate an unknown operator

I have a simple question but I can't seem to be able to solve it. Given that: 25 ╧ 17 = 267 35 ╧ 23 = 373 45 ╧ 15 = 465 what is ...
0
votes
3answers
79 views

Finding the $n$th term for the sequence $1, \frac{1}{2}, 3, \frac{1}{4}, 5, \frac{1}{6}, \dots$

I have tried using a negative exponent. I need one statement not two, the pattern is $$1, \; \frac{1}{2}, \; 3, \; \frac{1}{4}, \; 5, \; \frac{1}{6}, \dots$$
0
votes
2answers
26 views

Equation for value of p given x

I have a set of numbers: $\begin{array}{r(22)}x \in \{ 1,& 2,& 3,& 4,& 5,& 6,& 7,& 8,& 9,& 10,& 11,& 12,& 13,& 14,& 15,& 16,& 17,& ...
0
votes
1answer
40 views

Creating coexistent patterns, with several pattern-less systems

I'm a young musician, as well as a computer programmer. My understanding of math is formed well to my needs, but I am by no means a mathematician, but the field is very interesting to me. I have come ...
0
votes
1answer
38 views

How can I figure out the total solutions in this Combinatorics problem?

Imagine you have a sequence of cards, each having a unique set of features. Example features : letter (A, B, C), number (1, 2, 3), and color (Red, Green, Blue) Some example cards : A1Red, B1Blue, ...
1
vote
0answers
21 views

Trace of a product of a recursive series of non-full rank matrices

Let $H$ be a $m\times n$ matrix that is not full rank. Hence $H^T H \neq \mathbb{1}_{m\times m}$. Can we say anything about the diagonal entries, or the trace, of matrix products of the form: $P_0 = ...
2
votes
2answers
47 views

What is the relation between this binary number with no two 1 side by side and fibonacci sequence?

I saw this pattern of binary numbers with constraints first number should be 1 , and two 1's cannot be side by side. Now as an example ...
1
vote
1answer
41 views

T-shaped polygons

Is there any coefficient that can indicate T-shaped polygons ? Examples of T-shaped polygons:
3
votes
1answer
50 views
0
votes
0answers
15 views

Pattern embedding method

There are three defined functions; $a_n=A(n), b_n=B(n), c_n=C(n)$ and an unknown function $d_n=D(n)$. It has been found out that $d_1=a_1$$d_2=b_1$$d_3=c_1$$d_4=a_2$$d_5=b_2$..... Is there a method ...
0
votes
2answers
29 views

What is the general stragety for conjecturing a formula based off a pattern?

Is it simply to guess and evolve a answer until it gets closer or is there an approach? Ex: Find the formula for: $a_k = \frac{a_{k-1}}{2} + 1$ where $a_0 = 1$. One would go: $a_1 = 3/2, a_2 = ...
0
votes
0answers
21 views

How can I conceptually visualize a Gaussian Mixture Model?

I'm struggling to get my head around Gaussian Mixture Models & Processes from a conceptual level; my intention is to use a GMM for image segmentation but I'm struggling to understand it. The way ...
-1
votes
1answer
9k views

I don't see the pattern.. does anyone understand this..? [duplicate]

Note.. the numbers are actually in a 7 x 6 grid.. graphics did not show here.. ...
3
votes
1answer
585 views

Find the pattern, What is the correct answer

Ok, so this question is from seriously hard IQ test that has been doing the rounds on facebook, ok, 17 questions are easy 3 are hellishly hard, The answer to this one is 17, I do not know why, I ...
0
votes
1answer
102 views

Find the pattern, what is the correct number in that spot, explain the answer

we are given the following matrix: $\begin{pmatrix} 9 & 38 & 47 &4 \\ 6 & 35 & 42 & ? \\ 12 & 21 & 23 & 27\end{pmatrix}$ The number that goes in $?$ is $-5$. I ...
9
votes
2answers
133 views

Has anyone noticed this pattern?

I've been messing around a bit and I noticed a curious pattern when it comes to progressions of powers. Let's take the progression of consecutive integers: $1,2,3,4,5,6,7,...$ Obviously it's an ...
18
votes
9answers
3k views

Is the Look and Say Sequence a “proper” maths problem? [closed]

I once told my brother about the "Look and Say Sequence" (i.e. 1, 11, 21, 1211, 111221, ...). My brother then showed the sequence to his maths teacher at school and asked him to predict the next ...
1
vote
2answers
47 views

Estimating the mean with least median of squares target

I have a set of real numbers $x_1,\ldots,x_n$. I would like estimate the mean of the set, $y$, such that the median of squares will be minimal : $\operatorname{median}(x_i-y)^2$ Is there a closed ...
2
votes
2answers
85 views

Finding pattern- $6$ $11$ $25$

Finding pattern$$ \begin{matrix} 6 & 11 & (25) \\ 8 & 6 & (16) \\ 12 & 5 & (?) \\ \end{matrix} $$ Options are : $10/12/14/16$ My ...
1
vote
1answer
111 views

Can rainbows be considered to have mathematical patterns?

Of course it is evident that there is physics and mathematics involved in a rainbow, but my question is (as the title suggests) are there patterns to be found in rainbows? By patterns I mean ...
0
votes
1answer
37 views

what are the possible patterns of the sequence?

Given sequence 12, 10, 9 ,7 ,6, 8 what are the possible patterns you could think? I was thinking 12 + 6 = 18, 10 + 8 = 18, ..., which is very awkward.
0
votes
1answer
183 views

Find the next number in this sequence

I have a homework. It seems to be an easy sequence but I can't get the answer. So, What is the next element? $$2, 7, 10, 13, 23, 34,?$$ What would be the solution out of these numbers? 45 or 49 or 58 ...
0
votes
0answers
65 views

Number of differently-sized squares needed to fill a rectangle; is there a visible formula? [Pattern spotting]

Consider a game in which we tile a given rectangle with the largest squares that will fit. We record the number of squares of each size that we can use, until the rectangle is completely covered. ...
1
vote
2answers
202 views

In simple terms what is the sequence 220,171700,167167000,166716670000 a part of?

I know that <1,2,3,...,10>$\cdot$<1 0,9,8,...1>=220 <1,2,3,...,100>$\cdot$<100,99,98,...,1>=171700 <1,2,3,...,1000>$\cdot$<1000,999,998,...,1>=167167000 ...
2
votes
1answer
129 views

Mathematical Background for Computer Vision

I am a PhD student and would like to do deep research in the area of computer vision and pattern recognition. I know to be successful I need strong mathematical background. Could you please introduce ...
0
votes
2answers
80 views

Finding pattern (2,7,8,3,5)

What would replace $Z$ in the following sequencing? $$\begin{matrix} 2 & 3 & 4 \\ 7 & 6 & 5 \\ 8 & 7 & 1 \\ 3 & 0 & Z \\ 5 & ...
2
votes
1answer
181 views

Pattern of (1201, 2121, 3142, 4253, 5342)

What could be a part of the following set of numbers: $1201, 2121, 3142, 4253, 5342$ $a) 1317$ $b) 2315$ $c) 2573$ $d) 3456$ Differences between the numbers are $920, 1021, ...
0
votes
0answers
15 views

Finding properties of Inter arrival times

I apologise in advance if this is a bad question or if it's in the wrong place. Say I get a sample of inter arrival times, I'd like to have some kind of a measure which would tell me whether the ...
0
votes
3answers
1k views

Extract a Pattern of Iterated continued fractions from convergents

I have been working on an article at https://oeis.org/wiki/Table_of_convergents_constants where I posted a table of "convergents constants" (defined at https://oeis.org/wiki/Convergents_constant) ...
0
votes
1answer
48 views

Digit sum of the sum equals digit sum of the addends

This may be a simple question and I am not a mathematician. I recently noticed that 11+12+13 = 36 whose digit sum is 9. And that the digit sum 1+1+1+2+1+3 also equals 9. Is there a pattern here that ...
3
votes
0answers
80 views

Guilloché security printing — can it be cracked?

Money uses Security printing, and often uses Guilloché patterns. These curves are inscribed by wheels on wheels on wheels, ten wheels deep in some cases. For example, the back of the US $1 bill has ...
1
vote
1answer
65 views

Is there a shorter way to write an equation with a clear pattern?

I have this simple expression: $$\left(\begin{array}{l} 1\\ +(A)\\ +(A+B)\\ +(A+B+C)\\ +(A+B+C+D)\\ +(A+B+C+D+E)\\ +(A+B+C+D+E+F)\\ +(A+B+C+D+E+F+G)\\ +(A+B+C+D+E+F+G+H)\\ +(A+B+C+D+E+F+G+H) ...
1
vote
2answers
68 views

Number pattern problem

I need some help to figure out the following number pattern: Find the next number in the following sequence: $3, 2, 3, 12, 35, 78$. I tired to figure out the difference by ...
0
votes
1answer
73 views

Finding a generating function for a pattern

I was working on this projecteuler.com problem, and I was very interested by the premise. Essentially, given n terms, find an ...
5
votes
0answers
125 views

Point Group of a pattern

I need to determine the point group of the following patterns: I think the one on the left is $D_1$ and the one on the right is $D_2$
0
votes
0answers
65 views

What makes a pattern in a sequence?

Assume a stream of characters$(c)$ where $ c \in (A, B, C ... Z)$. I need to identify patterns available in the stream. As per the definition of a pattern I should be looking for a recurring string. ...
4
votes
1answer
80 views

the table at the end of Theoretical Computer Science Cheat Sheet

Theoretical Computer Science Cheat Sheet, created by Steve Seiden, is a hodgepodge of well-known mathematical theorems and notions. I can understand (or guess at least) many of them, but I'm not sure ...
1
vote
0answers
168 views

Study the number patterns and fill in the missing number

This problem seems easy but I have been working on it for quite some time with little clue. It is about finding number patterns, I have tried many different ways, which seem to work at first but fail ...
1
vote
1answer
72 views

Find pattern in recursion

this is a example from my book Write several elements of the recursion, and see if you can find a pattern. T(n) = T(n – 1) + n T(n –1) = T(n – 2) + (n –1) T(n –2) = T(n – 3) + (n –2) T(n –3) ...
0
votes
1answer
119 views

What is the 6th term of the sequence? [closed]

Sequence: ABC; 1A1B1C; 111A111B111C; 311A311B311C; ... What is the 6th term of the sequence? ...
3
votes
3answers
130 views

Largest number on multiplying with itself gives the same number as last digits of the product

What is the largest number on multiplying with itself gives the same number as last digits of the product? i.e., $(376 \times 376) = 141376$ i.e., $(25\times 25) = 625$ If the largest number cant ...
2
votes
1answer
69 views

Order a list of sets based on a rule (pretty tough)

I did not know where to turn so I'm looking up anyone who could offer an answer to this interesting problem. I have a set of variables, listed as (A, B, C, D, E, F, G, H) Each variable is couple in ...
0
votes
4answers
133 views

How to represent the $n$th number in the sequence $1,3,5,7,1,3,5,7,\dots$ as a closed form?

I'm given the repeating sequence $1,3,5,7,1,3,5,7,\dots.$ I must determine a formula for the $n$th term of the sequence. I have tried the triangle method, but since this is a repeating series it is ...
2
votes
1answer
91 views

Pattern finding for repeating sequences

Find a pattern for the following sequence. 1,1,3,1,3,5,7,1,3,5,7..... Let n= the nth number. Find the nth number of this series
0
votes
0answers
34 views

Creating feature vectors with a high degree of entropy from the actual training data for neural network?

Note: My upper level math skills are not in good shape and end around 1st semester calculus. I am looking for guidance that would help me find a known algorithm that does what I need in the open ...
-4
votes
2answers
539 views

How many pairs of integers $(A, B)$ are there in the range $[1,\ldots, N]$, such that $\gcd(A,B) = B$?

I am given a positive integer $N$ ($N\leq 10^9$). How many pairs of integers $(A, B)$ exist in the range $[1,\ldots, N]$ such that $\gcd(A,B) = B$?