Number of positive solutions to (x_1)^2 + (x_2)^2 + ... + (x_7)^2 <= n^2.

Terms

a(0) =1a(1) =71a(2) =491a(3) =2522a(4) =9263a(5) =27723a(6) =71480a(7) =163908a(8) =345657a(9) =679802a(10) =1252185a(11) =2203724a(12) =3715206a(13) =6041979a(14) =9510283a(15) =14591324a(16) =21788606a(17) =31894205a(18) =45741815a(19) =64467383a(20) =89363919a(21) =122254946a(22) =164721244a(23) =219526449a(24) =289133792a(25) =377013829a(26) =486522424a(27) =622759365