# A149984 (b-file synthesized from sequence entry) 0 1 1 2 2 5 3 17 4 55 5 200 6 737 7 2800 8 10875 9 42686 10 170295 11 683805 12 2774827 13 11322576 14 46519469 15 192043347 16 796633305 17 3317740288 18 13867861969 19 58155460455 20 244585944419 21 1031416896354 22 4359870977953 23 18470484019178 24 78406877383159 25 333459678106346 26 1420613236435519 27 6061821842982527