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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 16 |
| 3 | 45 |
| 4 | 220 |
| 5 | 795 |
| 6 | 3310 |
| 7 | 12774 |
| 8 | 51298 |
| 9 | 201637 |
| 10 | 802119 |
| 11 | 3169137 |
| 12 | 12571062 |
| 13 | 49748730 |
| 14 | 197152806 |
| 15 | 780649100 |
| 16 | 3092658411 |
| 17 | 12248195877 |
| 18 | 48517164179 |
| 19 | 192162096401 |
| 20 | 761151962411 |
| 21 | 3014780751286 |
| 22 | 11941310147017 |
| 23 | 47297795017905 |
[1,16,45,220,795,3310,12774,51298,201637,802119, 3169137,12571062,49748730,197152806,780649100, 3092658411,12248195877,48517164179,192162096401, 761151962411,3014780751286,11941310147017, 47297795017905] |