New posts in combinatorial-proofs

Combinatorial Geometric proof of $\binom{\binom{n}{2}}{3} > \binom{\binom{n}{3}}{2}$

combinatorics geometry euclidean-geometry combinatorial-proofs combinatorial-geometry

Strange inequality involving *nested* binomial coefficients and combinatorial interpretation

linear-algebra binomial-coefficients gamma-function combinatorial-proofs

Combinatorial proof for $\sum_{k = 0}^n \binom {r+k} k = \binom {r + n + 1} n$ [duplicate]

combinatorics summation binomial-coefficients combinatorial-proofs

How to show $\sum_{k=0}^{n}\binom{n+k}{k}\frac{1}{2^k}=2^{n}$

combinatorics binomial-coefficients generating-functions combinatorial-proofs

Multinomial sum with positive coefficients

probability combinatorics binomial-coefficients combinatorial-proofs multinomial-coefficients

Calculating $\sum_{k=1}^nk(k!)$ combinatorially [duplicate]

combinatorics summation factorial combinatorial-proofs

Is there a combinatorial proof that $e$ is finite?

combinatorics combinatorial-proofs

Combinatorial Proof for Binomial Identity: $\sum_{k = 0}^n \binom{k}{p} = \binom{n+1}{p+1}$ [duplicate]

combinatorics discrete-mathematics summation combinations combinatorial-proofs

Give the combinatorial proof of the identity $\sum\limits_{i=0}^{n} \binom{k-1+i}{k-1} = \binom{n+k}{k}$

combinatorics summation binomial-coefficients combinatorial-proofs

Combinatorial interpretation of an alternating binomial sum

combinatorics summation binomial-coefficients combinatorial-proofs algebraic-combinatorics

How to prove Double Factorial as Infinity Sum? [duplicate]

combinatorics combinatorial-proofs

Combinatorial proof of $\sum\limits_{k=0}^n {n \choose k}3^k=4^n$

combinatorics summation binomial-coefficients combinatorial-proofs

Show by combinatorial argument that ${2n\choose 2} = 2{n \choose 2} + n^2$

combinatorics discrete-mathematics combinatorial-proofs

Proof that ${n \choose k}={k-1 \choose k-1}+{k \choose k-1}+{k+1 \choose k-1}+\cdots+{n-1 \choose k-1}$ [duplicate]

combinatorics algebra-precalculus combinations binomial-coefficients combinatorial-proofs

Combinatorial proof of $\sum_{k=0}^{n}(-1)^{k}\binom{n}{k}(l-k)^n=n!$, using inclusion-exclusion

combinatorics summation binomial-coefficients inclusion-exclusion combinatorial-proofs

How to prove formula for power sum

combinatorics number-theory combinatorial-proofs

Is there a combinatorial interpretation of the triangular numbers?

combinatorics discrete-mathematics summation binomial-coefficients combinatorial-proofs

Show that $\sum\limits_{k=0}^n\binom{2n}{2k}^{\!2}-\sum\limits_{k=0}^{n-1}\binom{2n}{2k+1}^{\!2}=(-1)^n\binom{2n}{n}$

combinatorics summation binomial-coefficients binomial-theorem combinatorial-proofs

counting proof for $\sum_{k=0}^{n-1} 2^{k} = 2^n - 1$

combinatorics combinatorial-proofs

$\sum_{k=-m}^{n} \binom{m+k}{r} \binom{n-k}{s} =\binom{m+n+1}{r+s+1}$ using Counting argument

combinatorics discrete-mathematics summation binomial-coefficients combinatorial-proofs