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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 7 |
| 3 | 38 |
| 4 | 190 |
| 5 | 951 |
| 6 | 4757 |
| 7 | 23788 |
| 8 | 118940 |
| 9 | 594701 |
| 10 | 2973507 |
| 11 | 14867538 |
| 12 | 74337690 |
| 13 | 371688451 |
| 14 | 1858442257 |
| 15 | 9292211288 |
| 16 | 46461056440 |
| 17 | 232305282201 |
| 18 | 1161526411007 |
| 19 | 5807632055038 |
| 20 | 29038160275190 |
| 21 | 145190801375951 |
| 22 | 725954006879757 |
[1,7,38,190,951,4757,23788,118940,594701,2973507, 14867538,74337690,371688451,1858442257,9292211288, 46461056440,232305282201,1161526411007, 5807632055038,29038160275190,145190801375951, 725954006879757] |