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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 6 |
| 3 | 23 |
| 4 | 61 |
| 5 | 232 |
| 6 | 953 |
| 7 | 4343 |
| 8 | 19458 |
| 9 | 90165 |
| 10 | 421048 |
| 11 | 1984496 |
| 12 | 9408853 |
| 13 | 44826507 |
| 14 | 214397042 |
| 15 | 1027671976 |
| 16 | 4934720969 |
| 17 | 23725826486 |
| 18 | 114171204929 |
| 19 | 549741892899 |
| 20 | 2648230058688 |
| 21 | 12761166119581 |
| 22 | 61506635738385 |
| 23 | 296498879827182 |
[3,6,23,61,232,953,4343,19458,90165,421048, 1984496,9408853,44826507,214397042,1027671976, 4934720969,23725826486,114171204929,549741892899, 2648230058688,12761166119581,61506635738385, 296498879827182] |