Number of n X 3 0,1 arrays indicating 2 X 2 subblocks of some larger (n+1) X 4 binary array having a sum of three or less, with rows and columns of the latter in lexicographically nondecreasing order.
A227266
Number of n X 3 0,1 arrays indicating 2 X 2 subblocks of some larger (n+1) X 4 binary array having a sum of three or less, with rows and columns of the latter in lexicographically nondecreasing order.
Terms
- a(0) =4a(1) =16a(2) =49a(3) =132a(4) =341a(5) =836a(6) =1934a(7) =4232a(8) =8804a(9) =17501a(10) =33392a(11) =61393a(12) =109141a(13) =188181a(14) =315546a(15) =515823a(16) =823812a(17) =1287900a(18) =1974288a(19) =2972226a(20) =4400429a(21) =6414866a(22) =9218134a(23) =13070650a(24) =18303916a(25) =25336135a(26) =34690480a(27) =47016343a(28) =63113917a(29) =83962491
External references
- oeis: A227266