# A047144 (b-file synthesized from sequence entry) 2 1 3 4 4 13 5 42 6 148 7 540 8 1945 9 6994 10 25784 11 96564 12 361560 13 1353608 14 5113044 15 19462184 16 74227737 17 283335006 18 1085696746 19 4176869836 20 16100775648 21 62132631186 22 240258482330 23 931152718588 24 3614359486290 25 14044139747816