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

A334774

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

Terms

    a(0) =1a(1) =3a(2) =3a(3) =9a(4) =57a(5) =24a(6) =27a(7) =705a(8) =1449a(9) =339a(10) =81a(11) =7617a(12) =48615a(13) =49695a(14) =7392a(15) =243a(16) =78357a(17) =1290234a(18) =3650706a(19) =2234643a(20) =230217a(21) =729a(22) =791589a(23) =30630618a(24) =197457468a(25) =314306943a(26) =128203119a(27) =9689934a(28) =2187a(29) =7944321

External references