49402850domain: NAppears in sequencesa(n) = T(2*n, n), T given by A027907.at n=11A027908T(n,[ n/2 ]), T given by A027907.at n=22A027913Number of n X 1 0..2 arrays with rows and columns in lexicographic nondecreasing order but with exactly three mistakes.at n=20A278365