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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 5 |
| 4 | 9 |
| 5 | 25 |
| 6 | 53 |
| 7 | 125 |
| 8 | 273 |
| 9 | 609 |
| 10 | 1325 |
| 11 | 2885 |
| 12 | 6217 |
| 13 | 13353 |
| 14 | 28517 |
| 15 | 60685 |
| 16 | 128641 |
| 17 | 271857 |
| 18 | 572829 |
| 19 | 1203925 |
| 20 | 2524345 |
| 21 | 5281721 |
| 22 | 11029461 |
| 23 | 22991005 |
| 24 | 47846129 |
| 25 | 99420545 |
| 26 | 206297613 |
| 27 | 427508325 |
| 28 | 884842793 |
| 29 | 1829337929 |
| 30 | 3777980485 |
[1,1,5,9,25,53,125,273,609,1325,2885,6217,13353, 28517,60685,128641,271857,572829,1203925,2524345, 5281721,11029461,22991005,47846129,99420545, 206297613,427508325,884842793,1829337929, 3777980485] |