Irregular triangle read by rows: T(n,k) = number of 2-packed n X n matrices with exactly k nonzero entries (0 <= k <= n^2).

A230878

Irregular triangle read by rows: T(n,k) = number of 2-packed n X n matrices with exactly k nonzero entries (0 <= k <= n^2).

Terms

    a(0) =1a(1) =0a(2) =2a(3) =0a(4) =0a(5) =8a(6) =32a(7) =16a(8) =0a(9) =0a(10) =0a(11) =48a(12) =720a(13) =2880a(14) =4992a(15) =4608a(16) =2304a(17) =512a(18) =0a(19) =0a(20) =0a(21) =0a(22) =384a(23) =13824a(24) =143872a(25) =739328a(26) =2320896a(27) =4964352a(28) =7659520a(29) =8749056

External references