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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 8 |
| 5 | 15 |
| 6 | 39 |
| 7 | 87 |
| 8 | 254 |
| 9 | 633 |
| 10 | 1755 |
| 11 | 4817 |
| 12 | 13683 |
| 13 | 38328 |
| 14 | 109188 |
| 15 | 327645 |
| 16 | 962488 |
| 17 | 2855001 |
| 18 | 8585783 |
| 19 | 26100683 |
| 20 | 79038683 |
| 21 | 239634748 |
| 22 | 749702378 |
| 23 | 2323224093 |
| 24 | 7216147407 |
| 25 | 22570101754 |
| 26 | 71214487008 |
| 27 | 224091470121 |
| 28 | 704212414119 |
| 29 | 2258037023357 |
| 30 | 7208557781173 |
| 31 | 23017651439589 |
| 32 | 73774471716580 |
[1,1,2,3,8,15,39,87,254,633,1755,4817,13683,38328, 109188,327645,962488,2855001,8585783,26100683, 79038683,239634748,749702378,2323224093, 7216147407,22570101754,71214487008,224091470121, 704212414119,2258037023357,7208557781173, 23017651439589,73774471716580] |