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| n | a(n) |
|---|---|
| 2 | 2 |
| 3 | 9 |
| 4 | 30 |
| 5 | 154 |
| 6 | 986 |
| 7 | 6977 |
| 8 | 52590 |
| 9 | 415678 |
| 10 | 3409032 |
| 11 | 28787498 |
| 12 | 248930292 |
| 13 | 2195238596 |
| 14 | 19682012382 |
| 15 | 178974809121 |
| 16 | 1647460326046 |
| 17 | 15327261314934 |
| 18 | 143942130406288 |
| 19 | 1363094805806462 |
| 20 | 13004498819335396 |
| 21 | 124900418475706476 |
| 22 | 1206861624598185332 |
| 23 | 11725558427958257690 |
| 24 | 114494070652568918380 |
[2,9,30,154,986,6977,52590,415678,3409032, 28787498,248930292,2195238596,19682012382, 178974809121,1647460326046,15327261314934, 143942130406288,1363094805806462, 13004498819335396,124900418475706476, 1206861624598185332,11725558427958257690, 114494070652568918380] |