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| n | a(n) |
|---|---|
| 0 | 3 |
| 1 | 9 |
| 2 | 33 |
| 3 | 123 |
| 4 | 459 |
| 5 | 1713 |
| 6 | 6393 |
| 7 | 23859 |
| 8 | 89043 |
| 9 | 332313 |
| 10 | 1240209 |
| 11 | 4628523 |
| 12 | 17273883 |
| 13 | 64467009 |
| 14 | 240594153 |
| 15 | 897909603 |
| 16 | 3351044259 |
| 17 | 12506267433 |
| 18 | 46674025473 |
| 19 | 174189834459 |
| 20 | 650085312363 |
| 21 | 2426151414993 |
| 22 | 9054520347609 |
| 23 | 33791929975443 |
[3,9,33,123,459,1713,6393,23859,89043,332313, 1240209,4628523,17273883,64467009,240594153, 897909603,3351044259,12506267433,46674025473, 174189834459,650085312363,2426151414993, 9054520347609,33791929975443] |