Triangle read by rows: T(n, k) = number of k-element subobjects of an n-element set in the category of relations, n >= 0, 0 <= k <= n.

A373398

Triangle read by rows: T(n, k) = number of k-element subobjects of an n-element set in the category of relations, n >= 0, 0 <= k <= n.

Terms

    a(0) =1a(1) =1a(2) =1a(3) =1a(4) =3a(5) =1a(6) =1a(7) =7a(8) =9a(9) =1a(10) =1a(11) =15a(12) =55a(13) =25a(14) =1a(15) =1a(16) =31a(17) =285a(18) =395a(19) =65a(20) =1a(21) =1a(22) =63a(23) =1351a(24) =5045a(25) =2555a(26) =161a(27) =1a(28) =1a(29) =127

External references