A122108 a(n)=number of 1's ("live" cells) at stage n of a 2-dimensional cellular automaton evolving by the rule: 1 if N+S+E+W is 1 or 2, else 0, starting from a single live cell.

1, 4, 8, 12, 20, 24, 44, 28, 52, 56, 104, 56, 104, 112, 212, 60, 116, 120, 232, 120, 232, 240, 464, 120, 232, 240, 464, 240, 464, 480, 932, 124, 244, 248, 488, 248, 488, 496, 976, 248, 488, 496, 976, 496, 976, 992, 1952, 248, 488, 496, 976, 496, 976, 992, 1952