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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 18 |
| 5 | 43 |
| 6 | 108 |
| 7 | 263 |
| 8 | 651 |
| 9 | 1599 |
| 10 | 3942 |
| 11 | 9698 |
| 12 | 23890 |
| 13 | 58805 |
| 14 | 144806 |
| 15 | 356512 |
| 16 | 877820 |
| 17 | 2161285 |
| 18 | 5321485 |
| 19 | 13102246 |
| 20 | 32259890 |
| 21 | 79428762 |
| 22 | 195566238 |
| 23 | 481514453 |
| 24 | 1185564348 |
| 25 | 2919044646 |
| 26 | 7187145712 |
| 27 | 17695877607 |
| 28 | 43570023304 |
| 29 | 107276219947 |
| 30 | 264130857268 |
| 31 | 650331536681 |
| 32 | 1601218102939 |
[1,1,3,7,18,43,108,263,651,1599,3942,9698,23890, 58805,144806,356512,877820,2161285,5321485, 13102246,32259890,79428762,195566238,481514453, 1185564348,2919044646,7187145712,17695877607, 43570023304,107276219947,264130857268, 650331536681,1601218102939] |