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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 9 |
| 3 | 37 |
| 4 | 167 |
| 5 | 752 |
| 6 | 3503 |
| 7 | 16338 |
| 8 | 77337 |
| 9 | 367016 |
| 10 | 1755693 |
| 11 | 8417735 |
| 12 | 40551629 |
| 13 | 195740690 |
| 14 | 947789781 |
| 15 | 4596821237 |
| 16 | 22343646643 |
| 17 | 108754769594 |
| 18 | 530209557941 |
| 19 | 2587894918437 |
| 20 | 12647093223479 |
| 21 | 61866651654678 |
| 22 | 302941530380327 |
| 23 | 1484635126546032 |
| 24 | 7281810707827661 |
| 25 | 35741024226550076 |
| 26 | 175548055081259277 |
[1,2,9,37,167,752,3503,16338,77337,367016,1755693, 8417735,40551629,195740690,947789781,4596821237, 22343646643,108754769594,530209557941, 2587894918437,12647093223479,61866651654678, 302941530380327,1484635126546032,7281810707827661, 35741024226550076,175548055081259277] |