# A002043 (b-file synthesized from sequence entry) 2 3 3 0 4 6 5 18 6 40 7 81 8 201 9 414 10 916 11 1899 12 3973 13 8059 14 16402 15 32561 16 64520 17 125986 18 244448 19 469195 20 895077 21 1692143 22 3179406 23 5929721 24 10993373 25 20250589 26 37096872