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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 166 |
| 3 | 424 |
| 4 | 1446 |
| 5 | 5124 |
| 6 | 18271 |
| 7 | 62544 |
| 8 | 215035 |
| 9 | 739962 |
| 10 | 2537660 |
| 11 | 8744241 |
| 12 | 30188614 |
| 13 | 104165837 |
| 14 | 359665578 |
| 15 | 1242411171 |
| 16 | 4292458468 |
| 17 | 14835586385 |
| 18 | 51288707980 |
| 19 | 177340234374 |
| 20 | 613288580624 |
| 21 | 2121228689542 |
| 22 | 7337686991133 |
| 23 | 25384797504647 |
[3,166,424,1446,5124,18271,62544,215035,739962, 2537660,8744241,30188614,104165837,359665578, 1242411171,4292458468,14835586385,51288707980, 177340234374,613288580624,2121228689542, 7337686991133,25384797504647] |