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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 7 |
| 3 | 15 |
| 4 | 31 |
| 5 | 69 |
| 6 | 157 |
| 7 | 357 |
| 8 | 805 |
| 9 | 1811 |
| 10 | 4079 |
| 11 | 9199 |
| 12 | 20751 |
| 13 | 46797 |
| 14 | 105517 |
| 15 | 237917 |
| 16 | 536477 |
| 17 | 1209723 |
| 18 | 2727839 |
| 19 | 6151031 |
| 20 | 13869991 |
| 21 | 31275569 |
| 22 | 70523657 |
| 23 | 159024657 |
| 24 | 358586513 |
| 25 | 808580683 |
| 26 | 1823277559 |
| 27 | 4111329079 |
| 28 | 9270682359 |
| 29 | 20904566081 |
| 30 | 47137941057 |
| 31 | 106291873089 |
[1,3,7,15,31,69,157,357,805,1811,4079,9199,20751, 46797,105517,237917,536477,1209723,2727839, 6151031,13869991,31275569,70523657,159024657, 358586513,808580683,1823277559,4111329079, 9270682359,20904566081,47137941057,106291873089] |