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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 8 |
| 5 | 17 |
| 6 | 38 |
| 7 | 88 |
| 8 | 210 |
| 9 | 514 |
| 10 | 1285 |
| 11 | 3270 |
| 12 | 8447 |
| 13 | 22100 |
| 14 | 58455 |
| 15 | 156077 |
| 16 | 420153 |
| 17 | 1139155 |
| 18 | 3108095 |
| 19 | 8527675 |
| 20 | 23514124 |
| 21 | 65127571 |
| 22 | 181111940 |
| 23 | 505487115 |
| 24 | 1415502195 |
| 25 | 3975790024 |
| 26 | 11197966459 |
| 27 | 31619946886 |
| 28 | 89496047586 |
| 29 | 253858251337 |
| 30 | 721531869889 |
| 31 | 2054639741185 |
[1,1,2,4,8,17,38,88,210,514,1285,3270,8447,22100, 58455,156077,420153,1139155,3108095,8527675, 23514124,65127571,181111940,505487115,1415502195, 3975790024,11197966459,31619946886,89496047586, 253858251337,721531869889,2054639741185] |