OFFSET
0,2
FORMULA
G.f. A(x) satisfies: A(x) = 1 / ((1 - x) * (1 - x * A(x^2))).
MATHEMATICA
a[n_] := a[n] = 1 + Sum[a[k] a[n - 2 k - 1], {k, 0, Floor[(n - 1)/2]}]; Table[a[n], {n, 0, 34}]
nmax = 34; A[_] = 0; Do[A[x_] = 1/((1 - x) (1 - x A[x^2])) + O[x]^(nmax + 1) // Normal, nmax + 1]; CoefficientList[A[x], x]
CROSSREFS
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Feb 26 2022
STATUS
approved