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A108115 Let B(x) = Sum_{i >= 0} A108336(i)*x^i; sequence gives coefficients of B(x)^2. 1

%I

%S 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,

%T 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,

%U 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

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

%H Robert Israel, <a href="/A108115/b108115.txt">Table of n, a(n) for n = 0..10000</a>

%p S:= 0: SS:= 0:

%p for i from 0 to 100 do

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

%p if s = 0 or s = 3 then

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

%p fi

%p od:

%p seq(coeff(SS, x, i), i=0..100); # _Robert Israel_, May 14 2019

%Y Cf. A108336.

%Y a(n) mod 4 = A083952(n).

%K nonn

%O 0,2

%A _N. J. A. Sloane_, Jul 03 2005

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Last modified October 23 08:40 EDT 2021. Contains 348211 sequences. (Running on oeis4.)