69664

Appears in sequences

• Triangle of coefficients of di-Boustrophedon transform (see A063179) read by rows: Let the original sequence be (U0,U1,...) and the transformed sequence (V0,V2,...), then Vn is a linear combination of U0,...,Un. T(n,m) is the coefficient that goes with Um to get Vn.at n=58A063415
• Let A denote the sequence; then A is equal to the union of the self-convolutions A^2 and A^4, with terms in ascending order by size, where a(0)=1.at n=32A090847
• Numbers n such that sigma(n)=sigma(d_1)*sigma(d_2)*...*sigma(d_k) where d_1 d_2 ... d_k is the decimal expansion of n.at n=24A098771
• Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 0), (-1, 1, 0), (0, 1, 0), (1, -1, 1), (1, 1, -1)}.at n=10A148434
• E.g.f.: A(x) = exp( Sum_{n>=1} sigma(n) * a(n-1)*x^n/n! ) = Sum_{n>=0} a(n)*x^n/n! with a(0)=1.at n=6A156306