Number of positive solutions to (x_1)^2 + (x_2)^2 + ... + (x_6)^2 <= n^2.

Terms

a(0) =7a(1) =48a(2) =331a(3) =1269a(4) =3698a(5) =9382a(6) =20927a(7) =42683a(8) =79844a(9) =142173a(10) =238810a(11) =387615a(12) =603589a(13) =915324a(14) =1345294a(15) =1939221a(16) =2729723a(17) =3783313a(18) =5138567a(19) =6895632a(20) =9108626a(21) =11909496a(22) =15362753a(23) =19642539a(24) =24832744a(25) =31179476a(26) =38757032a(27) =47877886a(28) =58647957a(29) =71447776