a(n) = binomial(n+5,5)*binomial(n+8,8).

Terms

a(0) =1a(1) =54a(2) =945a(3) =9240a(4) =62370a(5) =324324a(6) =1387386a(7) =5096520a(8) =16563690a(9) =48668620a(10) =131405274a(11) =330142176a(12) =779502360a(13) =1743502320a(14) =3718285560a(15) =7601828256a(16) =14966099379a(17) =28482196050a(18) =52568991475a(19) =94362067800a(20) =165133618650a(21) =282337298100a(22) =472506635250a(23) =775303893000