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| n | a(n) |
|---|---|
| 0 | 3 |
| 1 | 15 |
| 2 | 199 |
| 3 | 2799 |
| 4 | 39443 |
| 5 | 555855 |
| 6 | 7833463 |
| 7 | 110394159 |
| 8 | 1555744931 |
| 9 | 21924550287 |
| 10 | 308974752679 |
| 11 | 4354269371247 |
| 12 | 61363142434739 |
| 13 | 864768558952911 |
| 14 | 12186870340755799 |
| 15 | 171745153272253359 |
| 16 | 2420342290330833731 |
| 17 | 34109007973445479695 |
| 18 | 480685905287198116999 |
| 19 | 6774132502524173020143 |
[3,15,199,2799,39443,555855,7833463,110394159, 1555744931,21924550287,308974752679,4354269371247, 61363142434739,864768558952911,12186870340755799, 171745153272253359,2420342290330833731, 34109007973445479695,480685905287198116999, 6774132502524173020143] |