Number of arrays of 8 integers in -n..n with sum zero.

Terms

a(0) =1a(1) =1107a(2) =38165a(3) =398567a(4) =2306025a(5) =9377467a(6) =30162301a(7) =82073295a(8) =197018321a(9) =429042211a(10) =864287973a(11) =1633586615a(12) =2927984825a(13) =5017519755a(14) =8273550157a(15) =13194953119a(16) =20438495649a(17) =30853690355a(18) =45522444469a(19) =65803811463a(20) =93384154505a(21) =130333031003a(22) =179165107485a(23) =242908414063