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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 12 |
| 4 | 122 |
| 5 | 1740 |
| 6 | 31922 |
| 7 | 715932 |
| 8 | 18978122 |
| 9 | 580513260 |
| 10 | 20125554242 |
| 11 | 779832497532 |
| 12 | 33398722757402 |
| 13 | 1566656717322060 |
| 14 | 79879485803841362 |
| 15 | 4398701789915269212 |
| 16 | 260166428897541369962 |
| 17 | 16449181879032096013740 |
| 18 | 1107112451498156565581282 |
| 19 | 79030557433744270179981372 |
[1,2,12,122,1740,31922,715932,18978122,580513260, 20125554242,779832497532,33398722757402, 1566656717322060,79879485803841362, 4398701789915269212,260166428897541369962, 16449181879032096013740,1107112451498156565581282, 79030557433744270179981372] |