Solution to the Dancing School Problem with 4 girls and n+4 boys: f(4,n).

Terms

a(0) =1a(1) =5a(2) =26a(3) =90a(4) =246a(5) =566a(6) =1146a(7) =2106a(8) =3590a(9) =5766a(10) =8826a(11) =12986a(12) =18486a(13) =25590a(14) =34586a(15) =45786a(16) =59526a(17) =76166a(18) =96090a(19) =119706a(20) =147446a(21) =179766a(22) =217146a(23) =260090a(24) =309126a(25) =364806a(26) =427706a(27) =498426a(28) =577590a(29) =665846