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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 10 |
| 5 | 32 |
| 6 | 122 |
| 7 | 544 |
| 8 | 2287 |
| 9 | 7688 |
| 10 | 25662 |
| 11 | 79456 |
| 12 | 256482 |
| 13 | 809784 |
| 14 | 2690604 |
| 15 | 8874432 |
| 16 | 30009480 |
| 17 | 98599568 |
| 18 | 332395712 |
| 19 | 1084222064 |
| 20 | 3637730112 |
| 21 | 11844968640 |
| 22 | 39726351272 |
| 23 | 129526799072 |
| 24 | 434837072968 |
| 25 | 1418856843552 |
| 26 | 4764806022144 |
[1,2,4,10,32,122,544,2287,7688,25662,79456,256482, 809784,2690604,8874432,30009480,98599568, 332395712,1084222064,3637730112,11844968640, 39726351272,129526799072,434837072968, 1418856843552,4764806022144] |