a(n) = n^7 + 7*n^5 + 14*n^3 + 7*n.

Terms

a(0) =0a(1) =29a(2) =478a(3) =4287a(4) =24476a(5) =101785a(6) =337434a(7) =946043a(8) =2333752a(9) =5206581a(10) =10714070a(11) =20633239a(12) =37597908a(13) =65378417a(14) =109216786a(15) =176222355a(16) =275832944a(17) =420346573a(18) =625528782a(19) =911300591a(20) =1302512140a(21) =1829807049a(22) =2530582538a(23) =3450050347a(24) =4642403496a(25) =6172093925a(26) =8115226054