A108115 - OEIS

A108115

Let B(x) = Sum_{i >= 0} A108336(i)*x^i; sequence gives coefficients of B(x)^2.

1, 2, 1, 2, 2, 2, 5, 2, 2, 2, 1, 2, 1, 2, 2, 2, 6, 2, 6, 6, 2, 6, 2, 2, 2, 2, 5, 2, 6, 6, 5, 14, 5, 6, 6, 2, 5, 2, 2, 2, 2, 6, 2, 6, 6, 2, 6, 2, 2, 2, 1, 2, 1, 2, 2, 2, 5, 2, 2, 2, 1, 2, 1, 2, 2, 2, 6, 2, 6, 6, 2, 6, 2, 2, 2, 2, 6, 2, 6, 6, 6, 14, 6, 10, 6, 6, 10, 6, 14, 10, 10, 18, 10, 18, 10, 10, 14

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OFFSET

0,2

LINKS

Robert Israel, Table of n, a(n) for n = 0..10000

MAPLE

S:= 0: SS:= 0:

for i from 0 to 100 do

s:= coeff(SS, x, i) mod 4;

if s = 0 or s = 3 then

SS:= SS + 2*expand(S*x^i)+x^(2*i); S:= S + x^i;

od: