The number of numbers [ [ ix ]jx ] that equal n, where i >= 1, j >= 1 and x=e.

Terms

a(0) =0a(1) =0a(2) =0a(3) =0a(4) =1a(5) =0a(6) =0a(7) =0a(8) =0a(9) =1a(10) =0a(11) =0a(12) =1a(13) =0a(14) =0a(15) =1a(16) =0a(17) =0a(18) =0a(19) =0a(20) =2a(21) =0a(22) =0a(23) =0a(24) =0a(25) =0a(26) =3a(27) =0a(28) =0a(29) =0