-2120

Appears in sequences

• exp(sinh(x)+arctan(x))=1+2*x+4/2!*x^2+7/3!*x^3+8/4!*x^4+17/5!*x^5...at n=8A013056
• cosh(sinh(x)+arctan(x))=1+4/2!*x^2+8/4!*x^4+214/6!*x^6-2120/8!*x^8...at n=4A013065
• Generalized Catalan numbers C(-1; n).at n=10A064310
• Expansion of 1/(1+x*c(x)), c(x) the g.f. of Catalan numbers A000108.at n=10A126983
• Triangle T(n,k), 0<=k<=n, read by rows given by :[ -1,1,1,1,1,1,1,...] DELTA [1,0,0,0,0,0,0,0,...] where DELTA is the operator defined in A084938.at n=55A127543
• Riordan array (1/(1+4x+x^2), x/(1+4x+x^2)).at n=32A159764
• Riordan array (1/(1+x*c(x)), x*c(x)) where c(x) is the g.f. of Catalan numbers (A000108).at n=55A237619
• Expansion of f(-x, -x^5)^2 / (f(x^2, x^10) * f(x^6, x^18)) in powers of x where f(, ) is Ramanujan's general theta function.at n=53A283023
• Square array T(n,k), n >= 0, k >= 0, read by antidiagonals downwards, where T(n,k) = n! * Sum_{j=0..n} (-k * (n-j))^j/j!.at n=50A351791
• Expansion of e.g.f. 1/(1 - x*exp(-4*x)).at n=5A351793
• G.f. A(x) satisfies: 1 = Sum_{n>=0} x^n * (1 + x^n*A(x))^n / (1 + x^(n+1)*A(x))^(n+1).at n=10A354124