Triangle read by rows: T(n,k) is the number of permutations of 2 indistinguishable copies of 1..n arranged in a circle with exactly k local maxima.

A334778

Triangle read by rows: T(n,k) is the number of permutations of 2 indistinguishable copies of 1..n arranged in a circle with exactly k local maxima.

Terms

    a(0) =1a(1) =0a(2) =1a(3) =0a(4) =4a(5) =2a(6) =0a(7) =18a(8) =66a(9) =6a(10) =0a(11) =72a(12) =1168a(13) =1192a(14) =88a(15) =0a(16) =270a(17) =16220a(18) =61830a(19) =33600a(20) =1480a(21) =0a(22) =972a(23) =202416a(24) =2150688a(25) =3821760a(26) =1268292a(27) =40272a(28) =0a(29) =3402

External references