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| n | a(n) |
|---|---|
| 1 | 5 |
| 2 | 16 |
| 3 | 18 |
| 4 | 196 |
| 5 | 497 |
| 6 | 2618 |
| 7 | 15694 |
| 8 | 74848 |
| 9 | 398520 |
| 10 | 2175661 |
| 11 | 11395331 |
| 12 | 60709714 |
| 13 | 325569321 |
| 14 | 1730448253 |
| 15 | 9227502184 |
| 16 | 49280674716 |
| 17 | 262657795284 |
| 18 | 1400914746703 |
| 19 | 7474498985522 |
| 20 | 39861303261615 |
| 21 | 212613780799718 |
| 22 | 1134133138126240 |
[5,16,18,196,497,2618,15694,74848,398520,2175661, 11395331,60709714,325569321,1730448253,9227502184, 49280674716,262657795284,1400914746703, 7474498985522,39861303261615,212613780799718, 1134133138126240] |