Triangle read by rows T(n, k) is the number of permutations on n elements whose square has k descents, for n >= 1 and 0 <= k <= n-1.

A373691

Triangle read by rows T(n, k) is the number of permutations on n elements whose square has k descents, for n >= 1 and 0 <= k <= n-1.

Terms

    a(0) =1a(1) =2a(2) =0a(3) =4a(4) =2a(5) =0a(6) =10a(7) =6a(8) =6a(9) =2a(10) =26a(11) =22a(12) =48a(13) =22a(14) =2a(15) =76a(16) =68a(17) =276a(18) =260a(19) =40a(20) =0a(21) =232a(22) =214a(23) =1384a(24) =2204a(25) =944a(26) =62a(27) =0a(28) =764a(29) =672

External references