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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 9 |
| 3 | 38 |
| 4 | 172 |
| 5 | 794 |
| 6 | 3743 |
| 7 | 17869 |
| 8 | 86041 |
| 9 | 417015 |
| 10 | 2031338 |
| 11 | 9935278 |
| 12 | 48749417 |
| 13 | 239814236 |
| 14 | 1182228047 |
| 15 | 5838360564 |
| 16 | 28875208718 |
| 17 | 142989086008 |
| 18 | 708834332504 |
| 19 | 3517098113362 |
| 20 | 17465002245262 |
| 21 | 86786509926071 |
| 22 | 431516545727561 |
| 23 | 2146705100234333 |
| 24 | 10684394235076090 |
| 25 | 53199409728104334 |
| 26 | 264986138128234705 |
[1,2,9,38,172,794,3743,17869,86041,417015,2031338, 9935278,48749417,239814236,1182228047,5838360564, 28875208718,142989086008,708834332504, 3517098113362,17465002245262,86786509926071, 431516545727561,2146705100234333, 10684394235076090,53199409728104334, 264986138128234705] |