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| n | a(n) |
|---|---|
| 1 | 13 |
| 2 | 169 |
| 3 | 699 |
| 4 | 2884 |
| 5 | 13876 |
| 6 | 58026 |
| 7 | 228110 |
| 8 | 919413 |
| 9 | 3634185 |
| 10 | 13998459 |
| 11 | 53800957 |
| 12 | 205790414 |
| 13 | 779790577 |
| 14 | 2941656860 |
| 15 | 11064045660 |
| 16 | 41445238814 |
| 17 | 154764854403 |
| 18 | 576618193508 |
| 19 | 2143459949578 |
| 20 | 7951565765308 |
| 21 | 29448392492010 |
| 22 | 108894241441660 |
[13,169,699,2884,13876,58026,228110,919413, 3634185,13998459,53800957,205790414,779790577, 2941656860,11064045660,41445238814,154764854403, 576618193508,2143459949578,7951565765308, 29448392492010,108894241441660] |