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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 25 |
| 4 | 96 |
| 5 | 422 |
| 6 | 1780 |
| 7 | 7537 |
| 8 | 31911 |
| 9 | 135283 |
| 10 | 573054 |
| 11 | 2427879 |
| 12 | 10286742 |
| 13 | 43582082 |
| 14 | 184647156 |
| 15 | 782310778 |
| 16 | 3314472134 |
| 17 | 14042671183 |
| 18 | 59495654829 |
| 19 | 252069704002 |
| 20 | 1067962669281 |
| 21 | 4524717892087 |
| 22 | 19170212756069 |
| 23 | 81219883046173 |
[1,5,25,96,422,1780,7537,31911,135283,573054, 2427879,10286742,43582082,184647156,782310778, 3314472134,14042671183,59495654829,252069704002, 1067962669281,4524717892087,19170212756069, 81219883046173] |