OFFSET
1,15
COMMENTS
a(n)=0 when n == 1 or 2 mod 4.
LINKS
Alois P. Heinz and Ray Chandler, Table of n, a(n) for n = 1..130 (first 100 terms from Alois P. Heinz)
FORMULA
a(n) is half the coefficient of x^0 in product(x^(k^3)+x^(k^-3), k=1..n).
a(n) = [x^(n^3)] Product_{k=1..n-1} (x^(k^3) + 1/x^(k^3)). - Ilya Gutkovskiy, Feb 01 2024
MAPLE
A113263:=proc(n) local i, p, t; t:= NULL; p:=1; for i to n do p:=p*(x^(i^3)+x^(-i^3)); t:=t, coeff(p, x, 0)/2; od; t; end;
MATHEMATICA
p = 1; t = {}; Do[p = Expand[p(x^(n^3) + x^(-n^3))]; AppendTo[t, Select[ p, NumberQ[ # ] &]/2], {n, 56}]; t (* Robert G. Wilson v *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Floor van Lamoen, Oct 21 2005
EXTENSIONS
More terms from Robert G. Wilson v and Tony Noe, Oct 27 2005
STATUS
approved