User Donald Splutterwit

4 votes

Proof for $\sqrt{2}$, $\sqrt{3}$, $\sqrt{5}$ can never be the terms of a single arithmetic progression with non zero common difference.

answered Jun 1 at 20:06

5 votes

Compute the following summation

answered Jan 9 at 20:45

3 votes

Accepted

Proving a Recursive Sequence Identity

answered Jan 9 at 22:41

2 votes

Combinatorial Interpretation of a partition identity

answered Nov 29, 2022 at 23:38

5 votes

How many sets of non-adjacent edges in the 600-cell?

answered Nov 4, 2022 at 0:17

2 votes

Deriving the integral form of the Legendre polynomials from the derivative form

answered Oct 17, 2022 at 19:07

6 votes

generating function for the number of partitions of n in which each odd part can occur any number of times but each even part can occur at most twice

answered Dec 1, 2019 at 21:55

7 votes

Accepted

Exponential generating function of the falling factorial

answered Nov 25, 2019 at 0:26

0 votes

Trying to explain the unknotting number of $7_5$

answered May 3, 2022 at 23:14

1 vote

Accepted

Recurrence Equations: Uneven amount of letters

answered May 6, 2022 at 0:29

6 votes

Accepted

Graph with minimal cycle 5

answered May 2, 2022 at 23:09

0 votes

Solving $(x+1)\sqrt{2(x^2 + 1)} + \sqrt{6x^2 + 18x +12} = \frac{3x^2 + 7x + 10}{2}$

answered Jan 27, 2022 at 1:25

1 vote

Find another sum of squares for $3^{12}-6^6+2^{12}$

answered Oct 7, 2021 at 21:38

3 votes

Find the sum of the series $3x+8x^2+15x^3 + ....$

answered Oct 6, 2021 at 19:42

2 votes

Calculate the value of $ abc \cdot (a + b + c) $

answered Oct 4, 2021 at 22:34

1 vote

Solving system of nonlinear equations by substitution

answered Sep 16, 2021 at 22:02

1 vote

Proving an alternating Euler sum: $\sum_{k=1}^{\infty} \frac{(-1)^{k+1} H_k}{k} = \frac{1}{2} \zeta(2) - \frac{1}{2} \log^2 2$

answered Sep 4, 2020 at 0:45

2 votes

Generating function of the number of permutations of length n with exactly k fixed points

answered Aug 3, 2021 at 22:04

3 votes

Accepted

The Probability the number of flips of a fair coin to achieve $3$ heads is $\mod 3$

answered Jul 15, 2021 at 1:09

2 votes

Accepted

I'm trying to find the point where a line intersects the YZ plane, but having trouble getting my solution to work.

answered Jul 8, 2021 at 22:05

0 votes

Determine whether my graph is planar or not

answered Jul 5, 2021 at 22:18

4 votes

Accepted

If $A, B$ are non-singular square matrices of the same order and $(A+B)^{-1}=A^{-1}+B^{-1}$, then choose the correct option

answered Jun 16, 2021 at 20:31

0 votes

Accepted

Trying to solve $y'=\frac{t+y}{t-y}$ by substitution

answered Jun 10, 2021 at 23:38

2 votes

Accepted

Distributing $5$ different balls to $4$ different persons

answered Aug 27, 2020 at 17:01

7 votes

Accepted

Prove that $\frac{(\sin 20^\circ + \cos 20^\circ)^2}{\cos 40^\circ} = \cot 25^\circ$

answered Jun 6, 2017 at 23:24

2 votes

Closed form of $\sum_{n=0}^{\infty} \frac{n^k}{2^n}$

answered Apr 13, 2021 at 23:32

1 vote

Where does the plus-minus come from in the quadratic formula?

answered Mar 28, 2021 at 1:10

4 votes

Accepted

Finding a generating function for Quicksort Algorithm

answered Mar 4, 2021 at 2:55

0 votes

Accepted

Need clarification on the complex form of Fourier series

answered Mar 4, 2021 at 2:27

7 votes

Accepted

Derivative of binomial coefficients

answered Mar 2, 2018 at 21:19

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1,386 Answers

Proof for $\sqrt{2}$, $\sqrt{3}$, $\sqrt{5}$ can never be the terms of a single arithmetic progression with non zero common difference.

Compute the following summation

Proving a Recursive Sequence Identity

Combinatorial Interpretation of a partition identity

How many sets of non-adjacent edges in the 600-cell?

Deriving the integral form of the Legendre polynomials from the derivative form

generating function for the number of partitions of n in which each odd part can occur any number of times but each even part can occur at most twice

Exponential generating function of the falling factorial

Trying to explain the unknotting number of $7_5$

Recurrence Equations: Uneven amount of letters

Graph with minimal cycle 5

Solving $(x+1)\sqrt{2(x^2 + 1)} + \sqrt{6x^2 + 18x +12} = \frac{3x^2 + 7x + 10}{2}$

Find another sum of squares for $3^{12}-6^6+2^{12}$

Find the sum of the series $3x+8x^2+15x^3 + ....$

Calculate the value of $ abc \cdot (a + b + c) $

Solving system of nonlinear equations by substitution

Proving an alternating Euler sum: $\sum_{k=1}^{\infty} \frac{(-1)^{k+1} H_k}{k} = \frac{1}{2} \zeta(2) - \frac{1}{2} \log^2 2$

Generating function of the number of permutations of length n with exactly k fixed points

The Probability the number of flips of a fair coin to achieve $3$ heads is $\mod 3$

I'm trying to find the point where a line intersects the YZ plane, but having trouble getting my solution to work.

Determine whether my graph is planar or not

If $A, B$ are non-singular square matrices of the same order and $(A+B)^{-1}=A^{-1}+B^{-1}$, then choose the correct option

Trying to solve $y'=\frac{t+y}{t-y}$ by substitution

Distributing $5$ different balls to $4$ different persons

Prove that $\frac{(\sin 20^\circ + \cos 20^\circ)^2}{\cos 40^\circ} = \cot 25^\circ$

Closed form of $\sum_{n=0}^{\infty} \frac{n^k}{2^n}$

Where does the plus-minus come from in the quadratic formula?

Finding a generating function for Quicksort Algorithm

Need clarification on the complex form of Fourier series

Derivative of binomial coefficients