43887domain: NAppears in sequencesNumber of permutations of [n] with exactly two (possibly overlapping) occurrences of the generalized pattern 12-3.at n=5A264451Number of 3 X n 0..1 arrays with every element equal to 1, 2 or 4 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.at n=12A302280