Number of upper triangular zero-one matrices with n ones and no zero rows or columns.
A138265
Number of upper triangular zero-one matrices with n ones and no zero rows or columns.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =2a(4) =5a(5) =16a(6) =61a(7) =271a(8) =1372a(9) =7795a(10) =49093a(11) =339386a(12) =2554596a(13) =20794982a(14) =182010945a(15) =1704439030a(16) =17003262470a(17) =180011279335
External references
- oeis: A138265