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| n | a(n) |
|---|---|
| 1 | 4 |
| 2 | 11 |
| 3 | 83 |
| 4 | 616 |
| 5 | 1674 |
| 6 | 4550 |
| 7 | 12367 |
| 8 | 33617 |
| 9 | 91380 |
| 10 | 248397 |
| 11 | 1835421 |
| 12 | 4989191 |
| 13 | 13562027 |
| 14 | 36865412 |
| 15 | 272400600 |
| 16 | 740461601 |
| 17 | 2012783315 |
| 18 | 5471312310 |
| 19 | 40427833596 |
| 20 | 298723530401 |
| 21 | 812014744422 |
| 22 | 2207284924203 |
| 23 | 6000022499693 |
[4,11,83,616,1674,4550,12367,33617,91380,248397, 1835421,4989191,13562027,36865412,272400600, 740461601,2012783315,5471312310,40427833596, 298723530401,812014744422,2207284924203, 6000022499693] |