a(n) = 13 + 165*n + 756*n^2 + 1470*n^3 + 1029*n^4.

Terms

a(0) =13a(1) =3433a(2) =31591a(3) =130351a(4) =370273a(5) =846613a(6) =1679323a(7) =3013051a(8) =5017141a(9) =7885633a(10) =11837263a(11) =17115463a(12) =23988361a(13) =32748781a(14) =43714243a(15) =57226963a(16) =73653853a(17) =93386521a(18) =116841271a(19) =144459103a(20) =176705713a(21) =214071493a(22) =257071531a(23) =306245611