Number T(n,k) of parity alternating permutations of [n] with exactly k descents from odd to even numbers; triangle T(n,k), n>=0, 0<=k<=max(0,floor((n-1)/2)), read by rows.

A232187

Number T(n,k) of parity alternating permutations of [n] with exactly k descents from odd to even numbers; triangle T(n,k), n>=0, 0<=k<=max(0,floor((n-1)/2)), read by rows.

Terms

    a(0) =1a(1) =1a(2) =2a(3) =1a(4) =1a(5) =5a(6) =3a(7) =2a(8) =8a(9) =2a(10) =20a(11) =44a(12) =8a(13) =6a(14) =66a(15) =66a(16) =6a(17) =114a(18) =594a(19) =414a(20) =30a(21) =24a(22) =624a(23) =1584a(24) =624a(25) =24a(26) =864a(27) =8784a(28) =14544a(29) =4464

External references