Irregular triangle T(n,k) for 1 <= k <= n/2 + 1: T(n,k) = number of double palindrome structures of length n using exactly k different symbols.

A284877

Irregular triangle T(n,k) for 1 <= k <= n/2 + 1: T(n,k) = number of double palindrome structures of length n using exactly k different symbols.

Terms

    a(0) =1a(1) =1a(2) =1a(3) =1a(4) =3a(5) =1a(6) =7a(7) =2a(8) =1a(9) =15a(10) =5a(11) =1a(12) =25a(13) =21a(14) =3a(15) =1a(16) =49a(17) =42a(18) =7a(19) =1a(20) =79a(21) =122a(22) =44a(23) =4a(24) =1a(25) =129a(26) =225a(27) =90a(28) =9a(29) =1

External references