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%I #3 Mar 02 2015 16:08:49
%S 0,1,30,220,950,3045,8036,18480,38340,73425,131890,224796,366730,
%T 576485,877800,1300160,1879656,2659905,3693030,5040700,6775230,
%U 8980741,11754380,15207600,19467500,24678225,31002426,38622780,47743570
%N Sum of squares of numbers that cannot be written as t*n + u*(n+1) for nonnegative integers t,u.
%D Fred. Schuh, Vragen betreffende een onbepaalde vergelijking, Nieuw Tijdschrift voor Wiskunde, 52 (1964-1965) 193-198.
%F n^2*(n^2-1)*(n^2-n-1)/12. G.f.:(1+23*x+31*x^2+5*x^3)*x^2/(1-x)^7
%p seq(n^2*(n^2-1)*(n^2-n-1)/12,n=1..40);
%Y Cf. A002417.
%K easy,nonn
%O 1,3
%A _Floor van Lamoen_, Oct 09 2002