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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 6 |
| 4 | 19 |
| 5 | 51 |
| 6 | 114 |
| 7 | 280 |
| 8 | 750 |
| 9 | 2064 |
| 10 | 5701 |
| 11 | 15378 |
| 12 | 40521 |
| 13 | 104947 |
| 14 | 267111 |
| 15 | 673050 |
| 16 | 1699517 |
| 17 | 4330599 |
| 18 | 11154867 |
| 19 | 29035169 |
| 20 | 76256925 |
| 21 | 201654330 |
| 22 | 535791945 |
| 23 | 1427841441 |
| 24 | 3811047033 |
| 25 | 10175838252 |
| 26 | 27152046705 |
| 27 | 72337813554 |
| 28 | 192304557673 |
| 29 | 509943239307 |
| 30 | 1348674768789 |
| 31 | 3557601342063 |
[1,3,6,19,51,114,280,750,2064,5701,15378,40521, 104947,267111,673050,1699517,4330599,11154867, 29035169,76256925,201654330,535791945,1427841441, 3811047033,10175838252,27152046705,72337813554, 192304557673,509943239307,1348674768789, 3557601342063] |