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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 11 |
| 3 | 43 |
| 4 | 159 |
| 5 | 647 |
| 6 | 2519 |
| 7 | 10043 |
| 8 | 39895 |
| 9 | 159703 |
| 10 | 637927 |
| 11 | 2551171 |
| 12 | 10200039 |
| 13 | 40803219 |
| 14 | 163198675 |
| 15 | 652774767 |
| 16 | 2611029851 |
| 17 | 10444211447 |
| 18 | 41776529287 |
| 19 | 167106121619 |
| 20 | 668423198491 |
| 21 | 2673693100831 |
| 22 | 10694768891659 |
| 23 | 42779072149475 |
| 24 | 171116268699455 |
| 25 | 684465093334979 |
| 26 | 2737860308070095 |
[1,3,11,43,159,647,2519,10043,39895,159703,637927, 2551171,10200039,40803219,163198675,652774767, 2611029851,10444211447,41776529287,167106121619, 668423198491,2673693100831,10694768891659, 42779072149475,171116268699455,684465093334979, 2737860308070095] |