# A145868 (b-file synthesized from sequence entry) 0 1 1 2 2 6 3 19 4 68 5 255 6 1020 7 4221 8 18186 9 80304 10 364476 11 1684782 12 7944156 13 37988379 14 184406508 15 905147815 16 4495346570 17 22527055980 18 113957354940 19 580759868910 20 2982724210440 21 15414453711930 22 80177422383240 23 419249099692710 24 2204316120027420 25 11642676960438000