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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 11 |
| 3 | 122 |
| 4 | 2127 |
| 5 | 50682 |
| 6 | 1528900 |
| 7 | 55742458 |
| 8 | 2381375519 |
| 9 | 116597648906 |
| 10 | 6434959707871 |
| 11 | 395148541757400 |
| 12 | 26718459567126420 |
| 13 | 1972367532078679140 |
| 14 | 157829428196155580220 |
| 15 | 13607551212801836305770 |
| 16 | 1257482733143493065605455 |
| 17 | 123990702648155791823769270 |
| 18 | 12993254659661472801817366105 |
[1,2,11,122,2127,50682,1528900,55742458, 2381375519,116597648906,6434959707871, 395148541757400,26718459567126420, 1972367532078679140,157829428196155580220, 13607551212801836305770,1257482733143493065605455, 123990702648155791823769270, 12993254659661472801817366105] |