Search: id:A157579 Results 1-1 of 1 results found. %I A157579 %S A157579 1,3,294,21630,1556655,102426933,6421722076,420393758436,26609856588945, %T A157579 1503958534048245,77827209776501394,3793522397195559678, %U A157579 177172760525971961023,8001788984919141620040,350900981113969220953080 %N A157579 Half the number of length n integer sequences with sum zero and sum of squares 4418. %H A157579 Ron Hardin, Table of n, a(n) for n=2..50 %F A157579 [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,0,4418)/2. %Y A157579 Sequence in context: A058455 A116532 A124357 this_sequence A104821 A119065 A119069 %Y A157579 Adjacent sequences: A157576 A157577 A157578 this_sequence A157580 A157581 A157582 %K A157579 nonn %O A157579 2,2 %A A157579 Ron Hardin (rhhardin(AT)att.net) Mar 02 2009 Search completed in 0.021 seconds