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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 19 |
| 4 | 73 |
| 5 | 309 |
| 6 | 1229 |
| 7 | 4959 |
| 8 | 19821 |
| 9 | 79597 |
| 10 | 318453 |
| 11 | 1274563 |
| 12 | 5097973 |
| 13 | 20397515 |
| 14 | 81591147 |
| 15 | 326371001 |
| 16 | 1305482159 |
| 17 | 5222040189 |
| 18 | 20888133573 |
| 19 | 83552798667 |
| 20 | 334211074959 |
| 21 | 1336845501841 |
| 22 | 5347382348679 |
| 23 | 21389531880435 |
| 24 | 85558125961121 |
| 25 | 342232529890275 |
| 26 | 1368930120480617 |
| 27 | 5475720508827645 |
| 28 | 21902882035220391 |
| 29 | 87611528574186091 |
| 30 | 350446114129452131 |
| 31 | 1401784457568941917 |
| 32 | 5607137830212707769 |
[1,2,5,19,73,309,1229,4959,19821,79597,318453, 1274563,5097973,20397515,81591147,326371001, 1305482159,5222040189,20888133573,83552798667, 334211074959,1336845501841,5347382348679, 21389531880435,85558125961121,342232529890275, 1368930120480617,5475720508827645, 21902882035220391,87611528574186091, 350446114129452131,1401784457568941917, 5607137830212707769] |