Number T(n,k) of ordered pairs (p,q) of permutations of [n] with equal up-down signatures and p(1)=q(1)=k if n>0; triangle T(n,k), n>=0, 0<=k<=n, read by rows.

A262372

Number T(n,k) of ordered pairs (p,q) of permutations of [n] with equal up-down signatures and p(1)=q(1)=k if n>0; triangle T(n,k), n>=0, 0<=k<=n, read by rows.

Terms

    a(0) =1a(1) =0a(2) =1a(3) =0a(4) =1a(5) =1a(6) =0a(7) =2a(8) =2a(9) =2a(10) =0a(11) =10a(12) =8a(13) =8a(14) =10a(15) =0a(16) =88a(17) =68a(18) =64a(19) =68a(20) =88a(21) =0a(22) =1216a(23) =952a(24) =852a(25) =852a(26) =952a(27) =1216a(28) =0a(29) =24176

External references