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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 21 |
| 4 | 62 |
| 5 | 232 |
| 6 | 780 |
| 7 | 2716 |
| 8 | 9427 |
| 9 | 32612 |
| 10 | 113008 |
| 11 | 391387 |
| 12 | 1355818 |
| 13 | 4696609 |
| 14 | 16268643 |
| 15 | 56353996 |
| 16 | 195208062 |
| 17 | 676193929 |
| 18 | 2342310759 |
| 19 | 8113674993 |
| 20 | 28105465903 |
| 21 | 97356282867 |
| 22 | 337238520190 |
| 23 | 1168181597226 |
| 24 | 4046537274472 |
| 25 | 14017053521933 |
[1,5,21,62,232,780,2716,9427,32612,113008,391387, 1355818,4696609,16268643,56353996,195208062, 676193929,2342310759,8113674993,28105465903, 97356282867,337238520190,1168181597226, 4046537274472,14017053521933] |