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| n | a(n) |
|---|---|
| 1 | 4 |
| 2 | 8 |
| 3 | 38 |
| 4 | 90 |
| 5 | 363 |
| 6 | 1163 |
| 7 | 3985 |
| 8 | 14650 |
| 9 | 50088 |
| 10 | 185178 |
| 11 | 665415 |
| 12 | 2425915 |
| 13 | 8953631 |
| 14 | 32773916 |
| 15 | 121530364 |
| 16 | 449147910 |
| 17 | 1665804417 |
| 18 | 6189859849 |
| 19 | 22993326811 |
| 20 | 85585457988 |
| 21 | 318520365520 |
| 22 | 1186296435208 |
| 23 | 4419902305187 |
| 24 | 16469639460901 |
[4,8,38,90,363,1163,3985,14650,50088,185178, 665415,2425915,8953631,32773916,121530364, 449147910,1665804417,6189859849,22993326811, 85585457988,318520365520,1186296435208, 4419902305187,16469639460901] |