50787

Appears in sequences

• Numbers k such that 11^k == -1 (mod k-1).at n=13A055694
• Positive integers n that are palindromic in base 2 and whose binary representation has the same number of 0's as 1's.at n=36A143905
• Number of representations of 1 as a sum of numbers d*k with d in {-1,1} and k in {1,2,...,n}, where the sum of the numbers k is 2n + 1.at n=20A236430
• T(n, k) = [x^k] M(n)*Sum_{k=0..n} E2(n, k)*binomial(-x + n - k, 2*n), where E2 are the second-order Eulerian numbers A340556 and M(n) are the Minkowski numbers A053657. Triangle read by rows, T(n, k) for n >= 0 and 0 <= k <= 2*n+1.at n=31A341111