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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 6 |
| 3 | 29 |
| 4 | 192 |
| 5 | 1577 |
| 6 | 15516 |
| 7 | 178229 |
| 8 | 2339952 |
| 9 | 34559057 |
| 10 | 567117876 |
| 11 | 10237161629 |
| 12 | 201592448712 |
| 13 | 4300618438937 |
| 14 | 98803485774636 |
| 15 | 2432074390036229 |
| 16 | 63857242954421472 |
| 17 | 1781444969999245217 |
| 18 | 52620896463516221796 |
| 19 | 1640684857196257578029 |
| 20 | 53847865360369426418232 |
[1,2,6,29,192,1577,15516,178229,2339952,34559057, 567117876,10237161629,201592448712,4300618438937, 98803485774636,2432074390036229,63857242954421472, 1781444969999245217,52620896463516221796, 1640684857196257578029,53847865360369426418232] |