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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 23 |
| 5 | 76 |
| 6 | 249 |
| 7 | 974 |
| 8 | 4151 |
| 9 | 16558 |
| 10 | 70308 |
| 11 | 342937 |
| 12 | 1680725 |
| 13 | 8012252 |
| 14 | 40903572 |
| 15 | 222539812 |
| 16 | 1202060807 |
| 17 | 6608077855 |
| 18 | 38523427818 |
| 19 | 228629565951 |
| 20 | 1349303611408 |
| 21 | 8257330774574 |
| 22 | 53118486147015 |
| 23 | 345693735519287 |
| 24 | 2252515985849693 |
| 25 | 15028013765653626 |
| 26 | 102689873016938288 |
[1,3,7,23,76,249,974,4151,16558,70308,342937, 1680725,8012252,40903572,222539812,1202060807, 6608077855,38523427818,228629565951,1349303611408, 8257330774574,53118486147015,345693735519287, 2252515985849693,15028013765653626, 102689873016938288] |