Search: id:A157590 Results 1-1 of 1 results found. %I A157590 %S A157590 1,3,186,26130,3296565,312282243,24263695547,1693530847881, %T A157590 116031418602660,7614709044887230,485263665372726339, %U A157590 30129597082995141381,1791597506670518058876,101387984322685789268190 %N A157590 Half the number of length n integer sequences with sum zero and sum of squares 6728. %H A157590 Ron Hardin, Table of n, a(n) for n=2..50 %F A157590 [cache enabling] count(n,s,ss)->count(n,t,tt) where t=s mod n, q=(t-s)/ n, tt=ss+2*q*s+n*q^2; count(n,t,tt)=sum[i^2<=tt]{ count(n-1,t-i,tt-i^2) }. a(n)=count(n,0,6728)/2. %Y A157590 Sequence in context: A042779 A103503 A157561 this_sequence A157236 A058856 A158469 %Y A157590 Adjacent sequences: A157587 A157588 A157589 this_sequence A157591 A157592 A157593 %K A157590 nonn %O A157590 2,2 %A A157590 Ron Hardin (rhhardin(AT)att.net) Mar 02 2009 Search completed in 0.001 seconds