Stirling numbers of the second kind S(n+3, n).

Terms

a(0) =0a(1) =1a(2) =15a(3) =90a(4) =350a(5) =1050a(6) =2646a(7) =5880a(8) =11880a(9) =22275a(10) =39325a(11) =66066a(12) =106470a(13) =165620a(14) =249900a(15) =367200a(16) =527136a(17) =741285a(18) =1023435a(19) =1389850a(20) =1859550a(21) =2454606a(22) =3200450a(23) =4126200a(24) =5265000a(25) =6654375a(26) =8336601a(27) =10359090a(28) =12774790a(29) =15642600