Number of n X 3 binary arrays with rows lexicographically nondecreasing and columns lexicographically nondecreasing and row sums nondecreasing and column sums nonincreasing.
A266930
Number of n X 3 binary arrays with rows lexicographically nondecreasing and columns lexicographically nondecreasing and row sums nondecreasing and column sums nonincreasing.
Terms
- a(0) =2a(1) =4a(2) =9a(3) =20a(4) =44a(5) =92a(6) =182a(7) =340a(8) =605a(9) =1028a(10) =1680a(11) =2651a(12) =4058a(13) =6045a(14) =8793a(15) =12518a(16) =17484a(17) =24001a(18) =32438a(19) =43222a(20) =56853a(21) =73901a(22) =95024a(23) =120965a(24) =152570a(25) =190786a(26) =236681a(27) =291440a(28) =356388a(29) =432986
External references
- oeis: A266930