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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 10 |
| 3 | 55 |
| 4 | 385 |
| 5 | 2365 |
| 6 | 15367 |
| 7 | 96613 |
| 8 | 611644 |
| 9 | 3832477 |
| 10 | 23970089 |
| 11 | 149170604 |
| 12 | 925530638 |
| 13 | 5722654098 |
| 14 | 35282873191 |
| 15 | 216928671076 |
| 16 | 1330360845060 |
| 17 | 8139139896353 |
| 18 | 49683631194244 |
| 19 | 302640125458942 |
| 20 | 1839793530751731 |
| 21 | 11163107720200726 |
| 22 | 67610680329079976 |
[1,1,10,55,385,2365,15367,96613,611644,3832477, 23970089,149170604,925530638,5722654098, 35282873191,216928671076,1330360845060, 8139139896353,49683631194244,302640125458942, 1839793530751731,11163107720200726, 67610680329079976] |