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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 22 |
| 5 | 114 |
| 6 | 697 |
| 7 | 4923 |
| 8 | 39612 |
| 9 | 357899 |
| 10 | 3588836 |
| 11 | 39556420 |
| 12 | 475392841 |
| 13 | 6187284605 |
| 14 | 86701097310 |
| 15 | 1301467245329 |
| 16 | 20835850494474 |
| 17 | 354382860600678 |
| 18 | 6381494425302865 |
| 19 | 121290065781743383 |
| 20 | 2426510081356069016 |
| 21 | 50969474697328055063 |
| 22 | 1121571023472780698152 |
[1,1,2,5,22,114,697,4923,39612,357899,3588836, 39556420,475392841,6187284605,86701097310, 1301467245329,20835850494474,354382860600678, 6381494425302865,121290065781743383, 2426510081356069016,50969474697328055063, 1121571023472780698152] |