87136domain: NAppears in sequencesNumber of achiral polyominoes with n cells.at n=20A030227Number of 4Xn 0..1 arrays avoiding 0 0 1 and 1 0 0 horizontally and 0 0 1 and 1 0 1 vertically.at n=7A209651Number of partitions of [n] such that the element sum of each block is one more than a multiple of eight.at n=20A375943