Number of nonzero elements in the character table of the symmetric group S_n.

Terms

a(0) =1a(1) =4a(2) =8a(3) =21a(4) =39a(5) =92a(6) =170a(7) =331a(8) =593a(9) =1176a(10) =2118a(11) =3699a(12) =6658a(13) =11347a(14) =19760a(15) =32746a(16) =54854a(17) =90245a(18) =149906a(19) =237953a(20) =387937a(21) =608531a(22) =970912a(23) =1510331a(24) =2380015a(25) =3610620a(26) =5634251a(27) =8474110a(28) =12934092a(29) =19440955