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| n | a(n) |
|---|---|
| 1 | 4 |
| 2 | 10 |
| 3 | 29 |
| 4 | 97 |
| 5 | 365 |
| 6 | 1511 |
| 7 | 6726 |
| 8 | 31544 |
| 9 | 153328 |
| 10 | 763187 |
| 11 | 3857651 |
| 12 | 19692114 |
| 13 | 101153422 |
| 14 | 521664456 |
| 15 | 2697067469 |
| 16 | 13966320059 |
| 17 | 72395025823 |
| 18 | 375501794607 |
| 19 | 1948456098176 |
| 20 | 10113010271486 |
| 21 | 52497770870256 |
| 22 | 272549948856853 |
| 23 | 1415076190551061 |
[4,10,29,97,365,1511,6726,31544,153328,763187, 3857651,19692114,101153422,521664456,2697067469, 13966320059,72395025823,375501794607, 1948456098176,10113010271486,52497770870256, 272549948856853,1415076190551061] |