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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 4 |
| 3 | 7 |
| 4 | 10 |
| 5 | 23 |
| 6 | 45 |
| 7 | 76 |
| 8 | 150 |
| 9 | 293 |
| 10 | 532 |
| 11 | 1010 |
| 12 | 1942 |
| 13 | 3625 |
| 14 | 6833 |
| 15 | 13005 |
| 16 | 24499 |
| 17 | 46186 |
| 18 | 87489 |
| 19 | 165230 |
| 20 | 311809 |
| 21 | 589569 |
| 22 | 1114002 |
| 23 | 2103636 |
| 24 | 3975125 |
| 25 | 7511104 |
| 26 | 14188028 |
| 27 | 26805754 |
| 28 | 50647041 |
| 29 | 95680777 |
| 30 | 180765515 |
| 31 | 341525717 |
| 32 | 645225728 |
| 33 | 1218995503 |
[1,4,7,10,23,45,76,150,293,532,1010,1942,3625, 6833,13005,24499,46186,87489,165230,311809,589569, 1114002,2103636,3975125,7511104,14188028,26805754, 50647041,95680777,180765515,341525717,645225728, 1218995503] |