# A018585 (b-file synthesized from sequence entry) 1 1 2 2 3 3 4 4 5 6 6 7 7 8 8 12 9 14 10 16 11 21 12 24 13 28 14 32 15 42 16 48 17 56 18 84 19 96 20 112 21 168 22 224 23 336 24 672