# A025471 (b-file synthesized from sequence entry) 0 1 1 5 2 15 3 43 4 137 5 483 6 1881 7 7772 8 33292 9 146014 10 650688 11 2935909 12 13377899 13 61448617 14 284148766 15 1321470026 16 6175996065 17 28988110806 18 136575209239 19 645621236243 20 3061130340023 21 14552991533455 22 69354804657255 23 331251331834172 24 1585299655420744 25 7600886382041555 26 36504944105963117