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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 9 |
| 3 | 23 |
| 4 | 63 |
| 5 | 171 |
| 6 | 461 |
| 7 | 1247 |
| 8 | 3371 |
| 9 | 9111 |
| 10 | 24629 |
| 11 | 66575 |
| 12 | 179959 |
| 13 | 486451 |
| 14 | 1314933 |
| 15 | 3554415 |
| 16 | 9607995 |
| 17 | 25971519 |
| 18 | 70204013 |
| 19 | 189769551 |
| 20 | 512968999 |
| 21 | 1386614411 |
| 22 | 3748178797 |
| 23 | 10131759903 |
| 24 | 27387316427 |
| 25 | 74031077351 |
| 26 | 200114546757 |
| 27 | 540932717135 |
| 28 | 1462203568951 |
| 29 | 3952505014627 |
| 30 | 10684077253253 |
| 31 | 28880293973327 |
[1,3,9,23,63,171,461,1247,3371,9111,24629,66575, 179959,486451,1314933,3554415,9607995,25971519, 70204013,189769551,512968999,1386614411, 3748178797,10131759903,27387316427,74031077351, 200114546757,540932717135,1462203568951, 3952505014627,10684077253253,28880293973327] |