Using an analytic method, we derive an alternative formula for the probability that a geometrically distributed word of length n possesses the restricted growth property. Equating our result with a previously known formula yields an algebraic identity involving alternating sums of binomial coefficients via a probabilistic argument. In addition, we consider refinements of our formula obtained by...

Motivated by recent works of Sun and Tauraso, we prove some variations on the Green-Krammer identity involving central q-binomial coefficients, such as n−1 ∑ k=0 (−1)kq−(k+1 2 ) [ 2k k ] q ≡ (n 5 ) q−bn 4/5c (mod Φn(q)), where ( n p ) is the Legendre symbol and Φn(q) is the nth cyclotomic polynomial. As consequences, we deduce that 3am−1 ∑

Elementary proofs abound: the first identity results from choosing x = y = 1 in the binomial expansion of (x+y). The second one may be obtained by comparing the coefficient of x in the identity (1 + x)(1 + x) = (1 + x). The reader is surely aware of many other proofs, including some combinatorial in nature. At the end of the previous century, the evaluation of these sums was trivialized by the ...

We answer a question on the conditioned binomial coefficients raised in and article of Barlotti and Pannone, thus giving an alternative proof of an extension of Frobenius’ generalization of Sylow’s theorem.

We describe efficient algorithms to search for cases in which binomial coefficients are equal or almost equal, give a conjecturally complete list of all cases where two binomial coefficients differ by 1, and give some identities for binomial coefficients that seem to be new.