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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 6 |
| 3 | 29 |
| 4 | 122 |
| 5 | 464 |
| 6 | 1648 |
| 7 | 5583 |
| 8 | 18280 |
| 9 | 58337 |
| 10 | 182480 |
| 11 | 561686 |
| 12 | 1706136 |
| 13 | 5125069 |
| 14 | 15249762 |
| 15 | 45005309 |
| 16 | 131871638 |
| 17 | 383966228 |
| 18 | 1111712440 |
| 19 | 3202612347 |
| 20 | 9184267060 |
| 21 | 26229945521 |
| 22 | 74631504716 |
| 23 | 211620269834 |
| 24 | 598168622352 |
| 25 | 1685884643929 |
| 26 | 4738755368478 |
| 27 | 13286692506173 |
[1,6,29,122,464,1648,5583,18280,58337,182480, 561686,1706136,5125069,15249762,45005309, 131871638,383966228,1111712440,3202612347, 9184267060,26229945521,74631504716,211620269834, 598168622352,1685884643929,4738755368478, 13286692506173] |