a(n) = 10*binomial(n+4, 5).

Terms

a(0) =0a(1) =10a(2) =60a(3) =210a(4) =560a(5) =1260a(6) =2520a(7) =4620a(8) =7920a(9) =12870a(10) =20020a(11) =30030a(12) =43680a(13) =61880a(14) =85680a(15) =116280a(16) =155040a(17) =203490a(18) =263340a(19) =336490a(20) =425040a(21) =531300a(22) =657800a(23) =807300a(24) =982800a(25) =1187550a(26) =1425060a(27) =1699110a(28) =2013760a(29) =2373360