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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 7 |
| 4 | 7 |
| 5 | 31 |
| 6 | 49 |
| 7 | 145 |
| 8 | 289 |
| 9 | 727 |
| 10 | 1591 |
| 11 | 3775 |
| 12 | 8545 |
| 13 | 19873 |
| 14 | 45505 |
| 15 | 105127 |
| 16 | 241639 |
| 17 | 557023 |
| 18 | 1281937 |
| 19 | 2953009 |
| 20 | 6798817 |
| 21 | 15657847 |
| 22 | 36054295 |
| 23 | 83027839 |
| 24 | 191190721 |
| 25 | 440274241 |
| 26 | 1013846401 |
| 27 | 2334669127 |
| 28 | 5376208327 |
| 29 | 12380215711 |
| 30 | 28508840689 |
[1,1,7,7,31,49,145,289,727,1591,3775,8545,19873, 45505,105127,241639,557023,1281937,2953009, 6798817,15657847,36054295,83027839,191190721, 440274241,1013846401,2334669127,5376208327, 12380215711,28508840689] |