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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 109 |
| 4 | 3889 |
| 5 | 292681 |
| 6 | 37275121 |
| 7 | 5709311029 |
| 8 | 1254902705569 |
| 9 | 350061261777361 |
| 10 | 120872805166945441 |
| 11 | 51564789352080559549 |
| 12 | 26284030671328082426449 |
| 13 | 15848108292907342195314841 |
| 14 | 11161807217694742818283238161 |
| 15 | 9067075855589680072656446948869 |
| 16 | 8422853639587133754025283126027329 |
| 17 | 8870217999823146934380010426752373921 |
| 18 | 10511235230699377130222779475407450044481 |
| 19 | 13925615313807886230641992889497147251058189 |
[1,1,1,109,3889,292681,37275121,5709311029, 1254902705569,350061261777361,120872805166945441, 51564789352080559549,26284030671328082426449, 15848108292907342195314841, 11161807217694742818283238161, 9067075855589680072656446948869, 8422853639587133754025283126027329, 8870217999823146934380010426752373921, 10511235230699377130222779475407450044481, 13925615313807886230641992889497147251058189] |