Triangle T(n, k) = Eulerian(n*f(n, k) + 1, f(n, k)), where f(n, k) = k if k <= floor(n/2) otherwise n-k, read by rows.

A157221

Triangle T(n, k) = Eulerian(n*f(n, k) + 1, f(n, k)), where f(n, k) = k if k <= floor(n/2) otherwise n-k, read by rows.

Terms

    a(0) =1a(1) =1a(2) =1a(3) =1a(4) =4a(5) =1a(6) =1a(7) =11a(8) =11a(9) =1a(10) =1a(11) =26a(12) =14608a(13) =26a(14) =1a(15) =1a(16) =57a(17) =152637a(18) =152637a(19) =57a(20) =1a(21) =1a(22) =120a(23) =1479726a(24) =251732291184a(25) =1479726a(26) =120a(27) =1a(28) =1a(29) =247

External references