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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 17 |
| 4 | 65 |
| 5 | 261 |
| 6 | 1085 |
| 7 | 4555 |
| 8 | 19567 |
| 9 | 84709 |
| 10 | 370249 |
| 11 | 1633547 |
| 12 | 7258227 |
| 13 | 32402035 |
| 14 | 145428535 |
| 15 | 655641593 |
| 16 | 2966918443 |
| 17 | 13471545253 |
| 18 | 61360832927 |
| 19 | 280227228003 |
| 20 | 1282967187347 |
| 21 | 5887316760711 |
| 22 | 27071579408811 |
| 23 | 124715117059779 |
| 24 | 575561899922933 |
| 25 | 2660508922424331 |
| 26 | 12316490711071187 |
| 27 | 57097128209758149 |
[1,1,5,17,65,261,1085,4555,19567,84709,370249, 1633547,7258227,32402035,145428535,655641593, 2966918443,13471545253,61360832927,280227228003, 1282967187347,5887316760711,27071579408811, 124715117059779,575561899922933,2660508922424331, 12316490711071187,57097128209758149] |