OFFSET
0,3
LINKS
Robert Israel, Table of n, a(n) for n = 0..10000
MAPLE
N:=100: # to get a(1)..a(N)
A:= 1:
for iter from 1 do
B:= convert(series(1 + x*subs(x=x^2, A)/(1-x)^2, x, N+1), polynom);
if B = A then break fi;
A:= B;
od:
seq(coeff(A, x, j), j=0..N); # Robert Israel, May 03 2019
MATHEMATICA
terms = 50; A[_] = 0; Do[A[x_] = 1 + x A[x^2]/(1 - x)^2 + O[x]^(terms + 1) // Normal, terms + 1]; CoefficientList[A[x], x]
a[0] = 1; a[1] = 1; a[2] = 1; a[n_] := a[n] = 2 a[n - 1] - a[n - 2] + a[Floor[n/2]]; Join[{1, 1}, Differences[Table[2 a[n + 1], {n, 50}]]]
CROSSREFS
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, May 03 2019
STATUS
approved