# A005956 (b-file synthesized from sequence entry) 4 1 5 1 6 3 7 10 8 27 9 79 10 234 11 686 12 2036 13 6080 14 18224 15 54920 16 166245 17 505201 18 1541014 19 4716540 20 14480699 21 44586619 22 137648341 23 425992838 24 1321362034 25 4107332002 26 12792440104 27 39915889304 28 124762916912 29 390594099694 30 1224682772872 31 3845389399882