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| n | a(n) |
|---|---|
| 2 | 6 |
| 3 | 10 |
| 4 | 23 |
| 5 | 63 |
| 6 | 184 |
| 7 | 572 |
| 8 | 1838 |
| 9 | 6077 |
| 10 | 20528 |
| 11 | 70543 |
| 12 | 245832 |
| 13 | 866716 |
| 14 | 3085892 |
| 15 | 11079822 |
| 16 | 40072026 |
| 17 | 145850388 |
| 18 | 533831488 |
| 19 | 1963625766 |
| 20 | 7255080464 |
| 21 | 26912893722 |
| 22 | 100195188748 |
| 23 | 374246851254 |
| 24 | 1402069725352 |
| 25 | 5267108601573 |
| 26 | 19836741317924 |
[6,10,23,63,184,572,1838,6077,20528,70543,245832, 866716,3085892,11079822,40072026,145850388, 533831488,1963625766,7255080464,26912893722, 100195188748,374246851254,1402069725352, 5267108601573,19836741317924] |