# A174313 (b-file synthesized from sequence entry) 0 1 1 6 2 18 3 54 4 162 5 474 6 1398 7 4074 8 11898 9 34554 10 100302 11 290322 12 839382 13 2422626 14 6984342 15 20110806 16 57851358 17 166258242 18 477419658 19 1369878582 20 3927963138 21 11255743434 22 32235116502 23 92267490414 24 263968559874 25 754837708494 26 2157584748150 27 6164626128066 28 17606866229010