902812500domain: NAppears in sequencesNumber of zig-zag paths from top to bottom of a rectangle of width 9 with n rows whose color is not that of the top right corner.at n=30A153364Number of zig-zag paths from top to bottom of a rectangle of width 9 with 2n-1 rows whose color is not that of the top right corner.at n=15A153367