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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 14 |
| 4 | 20 |
| 5 | 50 |
| 6 | 112 |
| 7 | 190 |
| 8 | 328 |
| 9 | 666 |
| 10 | 1340 |
| 11 | 2038 |
| 12 | 3740 |
| 13 | 5954 |
| 14 | 10792 |
| 15 | 19542 |
| 16 | 30048 |
| 17 | 48290 |
| 18 | 80164 |
| 19 | 124694 |
| 20 | 204484 |
| 21 | 347610 |
| 22 | 515184 |
| 23 | 810750 |
| 24 | 1240296 |
| 25 | 1932722 |
| 26 | 2887820 |
| 27 | 4557838 |
| 28 | 7126652 |
| 29 | 10463330 |
| 30 | 15768168 |
| 31 | 23499934 |
[1,2,4,14,20,50,112,190,328,666,1340,2038,3740, 5954,10792,19542,30048,48290,80164,124694,204484, 347610,515184,810750,1240296,1932722,2887820, 4557838,7126652,10463330,15768168,23499934] |