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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 3 |
| 3 | 15 |
| 4 | 35 |
| 5 | 231 |
| 6 | 5005 |
| 7 | 255255 |
| 8 | 1616615 |
| 9 | 10140585 |
| 10 | 462120945 |
| 11 | 6685349671 |
| 12 | 1236789689135 |
| 13 | 30425026352721 |
| 14 | 311494317420715 |
| 15 | 13367169186706335 |
| 16 | 1253429172199617105 |
| 17 | 33151040519900217915 |
| 18 | 3909612711980232366109 |
| 19 | 119065478046670712967865 |
| 20 | 7970583287524270870963077 |
[2,3,15,35,231,5005,255255,1616615,10140585, 462120945,6685349671,1236789689135,30425026352721, 311494317420715,13367169186706335, 1253429172199617105,33151040519900217915, 3909612711980232366109,119065478046670712967865, 7970583287524270870963077] |