OFFSET
0,2
REFERENCES
E. Grosswald, Representations of Integers as Sums of Squares. Springer-Verlag, NY, 1985, p. 121.
G. H. Hardy and E. M. Wright, An Introduction to the Theory of Numbers. 3rd ed., Oxford Univ. Press, 1954, p. 314.
LINKS
T. D. Noe, Table of n, a(n) for n = 0..10000
Shi-Chao Chen, Congruences for rs(n), Journal of Number Theory, Volume 130, Issue 9, September 2010, Pages 2028-2032.
Shaun Cooper, On the number of representations of certain integers as sums of 11 or 13 squares, J. Number Theory 103 (2) (2003) 135-162
FORMULA
G.f.: theta_3(0,q)^11, where theta_3 is the 3rd Jacobi theta function. - Ilya Gutkovskiy, Jan 13 2017
a(n) = (22/n)*Sum_{k=1..n} A186690(k)*a(n-k), a(0) = 1. - Seiichi Manyama, May 27 2017
MAPLE
(sum(x^(m^2), m=-10..10))^11;
# Alternative:
A008453list := proc(len) series(JacobiTheta3(0, x)^11, x, len+1);
seq(coeff(%, x, j), j=0..len-1) end: A008453list(29); # Peter Luschny, Oct 02 2018
MATHEMATICA
Table[SquaresR[11, n], {n, 0, 28}] (* Ray Chandler, Nov 28 2006 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
EXTENSIONS
Extended by Ray Chandler, Nov 28 2006
STATUS
approved