# A015640 (b-file synthesized from sequence entry) 1 0 2 0 3 0 4 0 5 1 6 6 7 21 8 56 9 126 10 251 11 461 12 786 13 1281 14 1981 15 2981 16 4311 17 6131 18 8436 19 11496 20 15246 21 20076 22 25851 23 33166 24 41656 25 52281 26 64436 27 79316 28 96151 29 116626 30 139246 31 166651 32 196751 33 232501 34 271601 35 317961 36 367616 37 426521 38 489506