Number of n X n upper triangular matrices A of nonnegative integers such that a_1i + a_2i + ... + a_{i-1,i} - a_ii - a_{i,i+1} - ... - a_in = -1.
A008608
Number of n X n upper triangular matrices A of nonnegative integers such that a_1i + a_2i + ... + a_{i-1,i} - a_ii - a_{i,i+1} - ... - a_in = -1.
Terms
- a(0) =1a(1) =2a(2) =7a(3) =40a(4) =357a(5) =4820a(6) =96030a(7) =2766572a(8) =113300265a(9) =6499477726a(10) =515564231770
External references
- oeis: A008608