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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 13 |
| 4 | 38 |
| 5 | 116 |
| 6 | 373 |
| 7 | 1212 |
| 8 | 4063 |
| 9 | 13790 |
| 10 | 47820 |
| 11 | 166683 |
| 12 | 589544 |
| 13 | 2096696 |
| 14 | 7543287 |
| 15 | 27220425 |
| 16 | 99068066 |
| 17 | 361665420 |
| 18 | 1329801449 |
| 19 | 4899090442 |
| 20 | 18150085724 |
| 21 | 67373439992 |
| 22 | 251310896362 |
| 23 | 938695649224 |
| 24 | 3520154347595 |
| 25 | 13218509615238 |
| 26 | 49811826743912 |
| 27 | 187895224773770 |
| 28 | 710859105078058 |
| 29 | 2692016339593940 |
[1,2,5,13,38,116,373,1212,4063,13790,47820,166683, 589544,2096696,7543287,27220425,99068066, 361665420,1329801449,4899090442,18150085724, 67373439992,251310896362,938695649224, 3520154347595,13218509615238,49811826743912, 187895224773770,710859105078058,2692016339593940] |