-2289

Appears in sequences

• E.g.f. tan(cos(x)*x) (odd powers only).at n=5A009633
• Row sums of triangle A161363.at n=27A161375
• A triangle sequence of polynomial coefficients:p(x,n)=Sum[Binomial[n, k]*(-x)^k*Sum[StirlingS2[n, m]*x^m, {m, 0, n - k}], {k, 0, n}].at n=51A174859
• First differences of number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 141", based on the 5-celled von Neumann neighborhood.at n=27A270285
• a(1) = 1; a(n+1) = a(n) +- (sum of digits of a(1) up to a(n)), with "+" when a(n) is odd, or "-" if even.at n=33A332058
• G.f. A(x) satisfies: R(x^2*A(x)) = x^3 - x^4, where R(A(x)) = x.at n=35A350433
• a(n) = Sum_{k=1..n} (-1)^(k-1) * binomial(k+2,3) * floor(n/k).at n=27A366938