Number of nondecreasing strings of numbers x(i=1..6) in -n..n with sum x(i)^3 equal to 0.

Terms

a(0) =4a(1) =10a(2) =20a(3) =37a(4) =62a(5) =106a(6) =148a(7) =197a(8) =280a(9) =366a(10) =470a(11) =637a(12) =778a(13) =922a(14) =1098a(15) =1327a(16) =1562a(17) =1900a(18) =2236a(19) =2589a(20) =2940a(21) =3358a(22) =3766a(23) =4323a(24) =4874a(25) =5420a(26) =6114a(27) =6773a(28) =7476a(29) =8294