Number of ordered triples (w,x,y) with all terms in {-n,...-1,1,...,n} and 3w+x+y>0.

Terms

a(0) =0a(1) =4a(2) =30a(3) =105a(4) =249a(5) =487a(6) =846a(7) =1346a(8) =2012a(9) =2871a(10) =3943a(11) =5253a(12) =6828a(13) =8688a(14) =10858a(15) =13365a(16) =16229a(17) =19475a(18) =23130a(19) =27214a(20) =31752a(21) =36771a(22) =42291a(23) =48337a(24) =54936a(25) =62108a(26) =69878a(27) =78273a(28) =87313a(29) =97023