

A157552


Half the number of length n integer sequences with sum zero and sum of squares 800.


1



1, 3, 42, 3410, 143445, 4303761, 117586819, 2875510809, 67804504560, 1524258428187, 33435072500775, 715914503534022, 14685555146992730, 286576099225123995, 5347457520977926782, 96148425385860533358
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OFFSET

2,2


LINKS



FORMULA

[cache enabling] count(n,s,ss)>count(n,t,tt) where t=s mod n, q=(ts)/n, tt=ss+2*q*s+n*q^2; count(n,t,tt)=sum[i^2<=tt]{ count(n1,ti,tti^2) }. a(n)=count(n,0,800)/2.


CROSSREFS



KEYWORD

nonn


AUTHOR



STATUS

approved



