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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 17 |
| 4 | 57 |
| 5 | 197 |
| 6 | 727 |
| 7 | 2749 |
| 8 | 10399 |
| 9 | 40301 |
| 10 | 159574 |
| 11 | 631160 |
| 12 | 2522298 |
| 13 | 10221848 |
| 14 | 41531613 |
| 15 | 169372736 |
| 16 | 696855374 |
| 17 | 2879429468 |
| 18 | 11915981127 |
| 19 | 49573590322 |
| 20 | 207133252404 |
| 21 | 866652990044 |
| 22 | 3636829064055 |
| 23 | 15317311427914 |
| 24 | 64620435352636 |
| 25 | 273084047111032 |
| 26 | 1157214293358466 |
| 27 | 4912795094807380 |
[1,2,5,17,57,197,727,2749,10399,40301,159574, 631160,2522298,10221848,41531613,169372736, 696855374,2879429468,11915981127,49573590322, 207133252404,866652990044,3636829064055, 15317311427914,64620435352636,273084047111032, 1157214293358466,4912795094807380] |