# A142974 (b-file synthesized from sequence entry) 1 1 2 2 3 2 4 2 5 4 6 12 7 34 8 86 9 200 10 440 11 934 12 1938 13 3964 14 8036 15 16202 16 32558 17 65296 18 130800 19 261838 20 523946 21 1048196 22 2096732 23 4193842 24 8388102 25 16776664 26 33553832 27 67108214 28 134217026 29 268434700 30 536870100 31 1073740954 32 2147482718