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| n | a(n) |
|---|---|
| 1 | 5 |
| 2 | 9 |
| 3 | 51 |
| 4 | 153 |
| 5 | 351 |
| 6 | 3249 |
| 7 | 6579 |
| 8 | 19551 |
| 9 | 47151 |
| 10 | 122451 |
| 11 | 246975 |
| 12 | 393471 |
| 13 | 3292289 |
| 14 | 10792495 |
| 15 | 15270849 |
| 16 | 25770879 |
| 17 | 58967271 |
| 18 | 60642945 |
| 19 | 242340175 |
| 20 | 481701375 |
| 21 | 5122147185 |
| 22 | 6644739375 |
| 23 | 6971026699 |
| 24 | 21061868751 |
| 25 | 92330654625 |
| 26 | 213089528575 |
| 27 | 1159484186575 |
| 28 | 1305664357375 |
[5,9,51,153,351,3249,6579,19551,47151,122451, 246975,393471,3292289,10792495,15270849,25770879, 58967271,60642945,242340175,481701375,5122147185, 6644739375,6971026699,21061868751,92330654625, 213089528575,1159484186575,1305664357375] |