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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 14 |
| 5 | 50 |
| 6 | 200 |
| 7 | 919 |
| 8 | 4633 |
| 9 | 25361 |
| 10 | 148606 |
| 11 | 923394 |
| 12 | 6043996 |
| 13 | 41447150 |
| 14 | 296571213 |
| 15 | 2206965193 |
| 16 | 17034374165 |
| 17 | 136066491764 |
| 18 | 1122656493744 |
| 19 | 9552206133005 |
| 20 | 83695193972045 |
| 21 | 754199756930791 |
| 22 | 6981787930209535 |
| 23 | 66327351641879318 |
| 24 | 646031757787129761 |
| 25 | 6445726513363688990 |
| 26 | 65825739028009602120 |
| 27 | 687540665329016479660 |
[1,1,2,5,14,50,200,919,4633,25361,148606,923394, 6043996,41447150,296571213,2206965193,17034374165, 136066491764,1122656493744,9552206133005, 83695193972045,754199756930791,6981787930209535, 66327351641879318,646031757787129761, 6445726513363688990,65825739028009602120, 687540665329016479660] |