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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 10 |
| 4 | 38 |
| 5 | 142 |
| 6 | 588 |
| 7 | 2437 |
| 8 | 10461 |
| 9 | 45436 |
| 10 | 201286 |
| 11 | 901394 |
| 12 | 4075139 |
| 13 | 18588924 |
| 14 | 85449323 |
| 15 | 395126467 |
| 16 | 1837179948 |
| 17 | 8584943255 |
| 18 | 40290867700 |
| 19 | 189791115778 |
| 20 | 897095411261 |
| 21 | 4253625142255 |
| 22 | 20224200143286 |
| 23 | 96397912640423 |
| 24 | 460545684750707 |
| 25 | 2204930841748683 |
| 26 | 10576608120323346 |
| 27 | 50823903382293844 |
[1,1,3,10,38,142,588,2437,10461,45436,201286, 901394,4075139,18588924,85449323,395126467, 1837179948,8584943255,40290867700,189791115778, 897095411261,4253625142255,20224200143286, 96397912640423,460545684750707,2204930841748683, 10576608120323346,50823903382293844] |