206742

Appears in sequences

• Number of n X 2 binary arrays indicating whether each 2 X 2 subblock of a larger binary array has lexicographically increasing rows and columns, for some larger (n+1) X 3 binary array with rows and columns of the latter in lexicographically nondecreasing order.at n=28A227085
• G.f. satisfies A(x) = 1 + x*A(x) / (1 - x^3*A(x)^4).at n=15A365756