Number of n-fold branched coverings of the Klein bottle with r cyclic branch points (n,r>=1); array read by downward antidiagonals.

A113950

Number of n-fold branched coverings of the Klein bottle with r cyclic branch points (n,r>=1); array read by downward antidiagonals.

Terms

    a(0) =1a(1) =1a(2) =0a(3) =1a(4) =4a(5) =5a(6) =1a(7) =0a(8) =13a(9) =0a(10) =1a(11) =4a(12) =23a(13) =104a(14) =44a(15) =1a(16) =0a(17) =49a(18) =0a(19) =1256a(20) =0a(21) =1a(22) =4a(23) =95a(24) =2720a(25) =27344a(26) =30608a(27) =1266a(28) =1a(29) =0

External references