# A007985 (b-file synthesized from sequence entry) 1 2 2 2 3 6 4 22 5 58 6 146 7 414 8 1206 9 3410 10 9634 11 27670 12 79926 13 230666 14 667058 15 1936174 16 5632662 17 16408866 18 47875650 19 139908774 20 409404630 21 1199368026 22 3517351890 23 10325547582 24 30339113718 25 89217594738 26 262561101282 27 773248631222 28 2278737199606