Number of permutations of 0..floor((n*6-1)/2) on even squares of an n X 6 array such that each row, column, diagonal and (downwards) antidiagonal of even squares is increasing.
A215784
Number of permutations of 0..floor((n*6-1)/2) on even squares of an n X 6 array such that each row, column, diagonal and (downwards) antidiagonal of even squares is increasing.
Terms
- a(0) =1a(1) =2a(2) =12a(3) =29a(4) =189a(5) =458a(6) =2988a(7) =7241a(8) =47241a(9) =114482a(10) =746892a(11) =1809989a(12) =11808549a(13) =28616378a(14) =186696108a(15) =452432081a(16) =2951712081a(17) =7153064162a(18) =46667304972a(19) =113091730349a(20) =737821743309
External references
- oeis: A215784