Number of nX4 binary arrays indicating whether each 2X2 subblock of a larger binary array has lexicographically nondecreasing rows and columns, for some larger (n+1)X5 binary array with rows and columns of the latter in lexicographically nondecreasing order.

A227254

Number of nX4 binary arrays indicating whether each 2X2 subblock of a larger binary array has lexicographically nondecreasing rows and columns, for some larger (n+1)X5 binary array with rows and columns of the latter in lexicographically nondecreasing order.

Terms

    a(0) =7a(1) =23a(2) =134a(3) =813a(4) =4578a(5) =22659a(6) =98821a(7) =388681a(8) =1403516a(9) =4714206a(10) =14875044a(11) =44432556a(12) =126415358a(13) =344289685a(14) =901306978a(15) =2275929413a(16) =5559947847a(17) =13174033412a(18) =30343762095a(19) =68072517741a(20) =148997133853a(21) =318682656840a(22) =666983823620

External references