-640
domain: Z
Appears in sequences
- E.g.f. tan(sin(x))*sin(x) (even powers only).at n=4A009665
- Expansion of e.g.f. arctan(arcsin(x) * exp(x)).at n=6A012319
- cos(arctanh(x)+arctan(x))=1-4/2!*x^2+16/4!*x^4-640/6!*x^6+21760/8!*x^8...at n=3A013179
- Expansion of tan(tanh(x))*x/2.at n=5A024303
- Binomial transform of A073145.at n=14A073498
- Expansion of (1-x)^(-1)/(1+x-2*x^2+2*x^3).at n=9A077900
- Expansion of phi(-x) / psi(x^4) in powers of x where phi(), psi() are Ramanujan theta functions.at n=81A093085
- Expansion of (sqrt(1-8*x)-4*x)/sqrt(1-8*x).at n=4A098580
- Expansion of psi(x^3) / psi(x) in powers of x where psi() is a Ramanujan theta function.at n=37A101195
- Coordination sequence for octagonal tiling is a(n)*sqrt(2) + A103909(n).at n=15A103908
- McKay-Thompson series of class 32d for the Monster group.at n=81A112172
- Triangle T, read by rows, where matrix power T^2 has powers of 2 in the secondary diagonal: [T^2](n+1,n) = 2^(n+1), with all 1's in the main diagonal and zeros elsewhere.at n=16A117250
- Coefficients for obtaining A120057 from Bell numbers.at n=43A120058
- Triangular array, see Mathematica code.at n=50A122773
- Expansion of chi(x) * chi(-x^2)^2 * chi(-x^3) * chi(-x^4) * chi(x^6)^2 * chi(-x^12) in powers of x where chi() is a Ramanujan theta function.at n=82A134178
- Matrix log of triangle A111636, where A111636(n,k) = (2^k)^(n-k)*C(n,k) for n>=k>=0.at n=18A134530
- Integral form of A053120 :Triangle of coefficients of Integral form Chebyshev's T(n, x) polynomials (powers of x in increasing order); Much improved version by use of the integro-differential recursive form over a previous attempt.at n=39A136265
- T(i,j) = (-1)^(i+j)*(i+1)*binomial(i,j)*2^(i-j)*4^j.at n=11A137337
- Triangle: signed version of A055134.at n=17A137370
- Triangular sequence from a Peters polynomials expansion: l0 = 2; m0 = 2; p(t) = (1 + t)^x/(1 + (1 + t)^l0)^m0.at n=19A137393