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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 7 |
| 2 | 35 |
| 3 | 140 |
| 4 | 483 |
| 5 | 1498 |
| 6 | 4277 |
| 7 | 11425 |
| 8 | 28889 |
| 9 | 69734 |
| 10 | 161735 |
| 11 | 362271 |
| 12 | 786877 |
| 13 | 1662927 |
| 14 | 3428770 |
| 15 | 6913760 |
| 16 | 13660346 |
| 17 | 26492361 |
| 18 | 50504755 |
| 19 | 94766875 |
| 20 | 175221109 |
| 21 | 319564227 |
| 22 | 575387295 |
| 23 | 1023624280 |
| 24 | 1800577849 |
| 25 | 3133695747 |
| 26 | 5399228149 |
| 27 | 9214458260 |
| 28 | 15584195428 |
[1,7,35,140,483,1498,4277,11425,28889,69734, 161735,362271,786877,1662927,3428770,6913760, 13660346,26492361,50504755,94766875,175221109, 319564227,575387295,1023624280,1800577849, 3133695747,5399228149,9214458260,15584195428] |