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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 11 |
| 4 | 45 |
| 5 | 198 |
| 6 | 914 |
| 7 | 4367 |
| 8 | 21414 |
| 9 | 107155 |
| 10 | 544987 |
| 11 | 2808978 |
| 12 | 14640073 |
| 13 | 77025373 |
| 14 | 408544815 |
| 15 | 2182206259 |
| 16 | 11727989593 |
| 17 | 63373962690 |
| 18 | 344109933186 |
| 19 | 1876562458845 |
| 20 | 10273572074493 |
| 21 | 56443282489240 |
| 22 | 311097732946200 |
| 23 | 1719707775782826 |
| 24 | 9531914043637385 |
| 25 | 52963938340248863 |
| 26 | 294966593345731623 |
[1,1,3,11,45,198,914,4367,21414,107155,544987, 2808978,14640073,77025373,408544815,2182206259, 11727989593,63373962690,344109933186, 1876562458845,10273572074493,56443282489240, 311097732946200,1719707775782826,9531914043637385, 52963938340248863,294966593345731623] |