Irregular triangle read by rows: T(n,k) is the number of free polyominoes with n cells and width k, n >= 1, 1 <= k <= ceiling(n/2).

A379623

Irregular triangle read by rows: T(n,k) is the number of free polyominoes with n cells and width k, n >= 1, 1 <= k <= ceiling(n/2).

Terms

    a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =4a(6) =1a(7) =5a(8) =6a(9) =1a(10) =12a(11) =22a(12) =1a(13) =18a(14) =71a(15) =18a(16) =1a(17) =37a(18) =193a(19) =138a(20) =1a(21) =60a(22) =490a(23) =661a(24) =73a(25) =1a(26) =117a(27) =1221a(28) =2547a(29) =769

External references