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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 9 |
| 3 | 39 |
| 4 | 178 |
| 5 | 840 |
| 6 | 4007 |
| 7 | 19340 |
| 8 | 94128 |
| 9 | 460168 |
| 10 | 2259995 |
| 11 | 11132979 |
| 12 | 54970170 |
| 13 | 271972002 |
| 14 | 1347631186 |
| 15 | 6685969540 |
| 16 | 33205872514 |
| 17 | 165056176495 |
| 18 | 821039167010 |
| 19 | 4086584248983 |
| 20 | 20350736261471 |
| 21 | 101389521255599 |
| 22 | 505325574326270 |
| 23 | 2519374282327881 |
| 24 | 12564325986981825 |
| 25 | 62675050088092712 |
| 26 | 312713124134785503 |
[1,2,9,39,178,840,4007,19340,94128,460168,2259995, 11132979,54970170,271972002,1347631186,6685969540, 33205872514,165056176495,821039167010, 4086584248983,20350736261471,101389521255599, 505325574326270,2519374282327881, 12564325986981825,62675050088092712, 312713124134785503] |