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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 6 |
| 3 | 15 |
| 4 | 38 |
| 5 | 89 |
| 6 | 210 |
| 7 | 474 |
| 8 | 1065 |
| 9 | 2339 |
| 10 | 5091 |
| 11 | 10919 |
| 12 | 23230 |
| 13 | 48887 |
| 14 | 102126 |
| 15 | 211599 |
| 16 | 435561 |
| 17 | 890617 |
| 18 | 1810786 |
| 19 | 3661118 |
| 20 | 7365473 |
| 21 | 14747049 |
| 22 | 29397160 |
| 23 | 58356179 |
| 24 | 115392801 |
| 25 | 227332038 |
| 26 | 446304671 |
| 27 | 873298579 |
| 28 | 1703463864 |
| 29 | 3312873935 |
| 30 | 6424553973 |
| 31 | 12425158365 |
| 32 | 23968214357 |
| 33 | 46120280910 |
| 34 | 88535346223 |
[1,2,6,15,38,89,210,474,1065,2339,5091,10919, 23230,48887,102126,211599,435561,890617,1810786, 3661118,7365473,14747049,29397160,58356179, 115392801,227332038,446304671,873298579, 1703463864,3312873935,6424553973,12425158365, 23968214357,46120280910,88535346223] |