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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 22 |
| 3 | 198 |
| 4 | 1134 |
| 5 | 4884 |
| 6 | 17226 |
| 7 | 52338 |
| 8 | 141570 |
| 9 | 348777 |
| 10 | 795652 |
| 11 | 1701700 |
| 12 | 3444948 |
| 13 | 6651216 |
| 14 | 12321804 |
| 15 | 22011804 |
| 16 | 38073948 |
| 17 | 63985977 |
| 18 | 104782986 |
| 19 | 167620090 |
| 20 | 262495090 |
| 21 | 403165620 |
| 22 | 608300550 |
| 23 | 902911230 |
| 24 | 1320114510 |
| 25 | 1903286385 |
| 26 | 2708672616 |
| 27 | 3808530792 |
| 28 | 5294887048 |
[1,22,198,1134,4884,17226,52338,141570,348777, 795652,1701700,3444948,6651216,12321804,22011804, 38073948,63985977,104782986,167620090,262495090, 403165620,608300550,902911230,1320114510, 1903286385,2708672616,3808530792,5294887048] |