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| n | a(n) |
|---|---|
| 2 | 4 |
| 3 | 10 |
| 4 | 29 |
| 5 | 91 |
| 6 | 300 |
| 7 | 1023 |
| 8 | 3575 |
| 9 | 12727 |
| 10 | 45968 |
| 11 | 167960 |
| 12 | 619514 |
| 13 | 2302990 |
| 14 | 8617640 |
| 15 | 32427585 |
| 16 | 122611275 |
| 17 | 465542655 |
| 18 | 1774086600 |
| 19 | 6782469540 |
| 20 | 26004015510 |
| 21 | 99953651850 |
| 22 | 385077767880 |
| 23 | 1486591659150 |
| 24 | 5749679124774 |
| 25 | 22275652390326 |
| 26 | 86434602692480 |
| 27 | 335860170462208 |
| 28 | 1306751215490420 |
[4,10,29,91,300,1023,3575,12727,45968,167960, 619514,2302990,8617640,32427585,122611275, 465542655,1774086600,6782469540,26004015510, 99953651850,385077767880,1486591659150, 5749679124774,22275652390326,86434602692480, 335860170462208,1306751215490420] |