-199360981

Appears in sequences

• Expansion of e.g.f. Gudermannian(x) = 2*arctan(exp(x)) - Pi/2.at n=7A028296
• Expansion of e.g.f.: (1+x)*sech(x).at n=14A119882
• Euler (or secant) numbers E(n).at n=14A122045
• Expansion of e.g.f. 2*exp(x)*(1-exp(x))/(1+exp(2*x)).at n=14A163747
• Numerators of generalized Bernoulli numbers associated with the zigzag numbers A000111.at n=15A185424
• a(n) = E(n) - E(n+1), where E(n) are the Euler numbers A122045(n).at n=14A241209
• Generalized Worpitzky numbers W_{m}(n,k) for m = 2, n >= 0 and 0 <= k <= n, triangle read by rows.at n=28A318259
• A(n, k) = (m*k)! [x^k] MittagLefflerE(m, x)^(-n), for m = 2, n >= 0, k >= 0; square array read by descending antidiagonals.at n=37A326327
• Triangle with Euler (secant) numbers, read by rows, T(n, k) for 0 <= k <= n.at n=28A326724
• a(n) = (4^n*(Z(-n, 1/4) - Z(-n, 3/4)) + Z(-n, 1)*(2^(n+1)-1))*A171977(n+1), where Z(n, c) is the Hurwitz zeta function.at n=14A335955
• a(n) = numerator(4^(n + 1)*zeta(-n, 1/4)).at n=14A344917
• a(n) = permanent(T(n)), where T(n) is the tangent matrix defined in A346831 and n >= 1; by convention a(0) = 1.at n=14A347598