Number of conjugacy classes of the symmetric group S_n when conjugating only by even permutations.

Terms

a(0) =1a(1) =2a(2) =4a(3) =6a(4) =8a(5) =12a(6) =16a(7) =24a(8) =32a(9) =44a(10) =58a(11) =80a(12) =104a(13) =138a(14) =180a(15) =236a(16) =302a(17) =390a(18) =496a(19) =634a(20) =800a(21) =1010a(22) =1264a(23) =1586a(24) =1970a(25) =2448a(26) =3024a(27) =3734a(28) =4582a(29) =5622