OFFSET
1,1
LINKS
J. O. Sizemore, Lagrange's Four Square Theorem
R. C. Vaughan, Lagrange's four-square theorem
Eric Weisstein's World of Math, Lagrange's Four-Square Theorem
Wikipedia, Lagrange's four-square theorem
EXAMPLE
a(6) = 55 since 55 == 7 (mod 8) and all its representations as a sum of squares have duplicates, namely, 55=1^2+1^2+2^2+7^2, 55=1^2+2^2+5^2+5^2, 55=1^2+3^2+3^2+6^2.
CROSSREFS
KEYWORD
nonn,fini,full
AUTHOR
Walter Kehowski, Jun 08 2014
STATUS
approved