Triangular array read by rows. Let P be the poset of all even sized subsets of [2n] ordered by inclusion. T(n,k) is the number of intervals in P with length k, 0<=k<=n, n>=0.
A328821
Triangular array read by rows. Let P be the poset of all even sized subsets of [2n] ordered by inclusion. T(n,k) is the number of intervals in P with length k, 0<=k<=n, n>=0.
Terms
- a(0) =1a(1) =2a(2) =1a(3) =8a(4) =12a(5) =1a(6) =32a(7) =120a(8) =30a(9) =1a(10) =128a(11) =896a(12) =560a(13) =56a(14) =1a(15) =512a(16) =5760a(17) =6720a(18) =1680a(19) =90a(20) =1a(21) =2048a(22) =33792a(23) =63360a(24) =29568a(25) =3960a(26) =132a(27) =1a(28) =8192a(29) =186368
External references
- oeis: A328821