703365domain: NAppears in sequencesSum of squares of numbers that can be written as t*n + u*(n+1) for nonnegative integers t,u in exactly one way.at n=8A076460Number of active (ON, black) cells at stage 2^n-1 of the two-dimensional cellular automaton defined by "Rule 451", based on the 5-celled von Neumann neighborhood.at n=9A272257