a(n) = binomial(n+4,4)*(2*n+1).

Terms

a(0) =1a(1) =15a(2) =75a(3) =245a(4) =630a(5) =1386a(6) =2730a(7) =4950a(8) =8415a(9) =13585a(10) =21021a(11) =31395a(12) =45500a(13) =64260a(14) =88740a(15) =120156a(16) =159885a(17) =209475a(18) =270655a(19) =345345a(20) =435666a(21) =543950a(22) =672750a(23) =824850a(24) =1003275a(25) =1211301a(26) =1452465a(27) =1730575a(28) =2049720a(29) =2414280