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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 13 |
| 4 | 7 |
| 5 | 115 |
| 6 | 237 |
| 7 | 15 |
| 8 | 1935 |
| 9 | 7825 |
| 10 | 31473 |
| 11 | 31711 |
| 12 | 254649 |
| 13 | 15957 |
| 14 | 2050541 |
| 15 | 8219801 |
| 16 | 16490635 |
| 17 | 33035745 |
| 18 | 132455435 |
| 19 | 530485275 |
| 20 | 1061920785 |
| 21 | 4253619813 |
| 22 | 4256987887 |
| 23 | 34095896991 |
| 24 | 136471574881 |
| 25 | 273072139013 |
| 26 | 136638599097 |
| 27 | 2187167322891 |
| 28 | 4377196161075 |
| 29 | 4378797345767 |
| 30 | 35049397190341 |
[1,3,13,7,115,237,15,1935,7825,31473,31711,254649, 15957,2050541,8219801,16490635,33035745,132455435, 530485275,1061920785,4253619813,4256987887, 34095896991,136471574881,273072139013, 136638599097,2187167322891,4377196161075, 4378797345767,35049397190341] |