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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 7 |
| 3 | 35 |
| 4 | 119 |
| 5 | 387 |
| 6 | 1050 |
| 7 | 2786 |
| 8 | 7160 |
| 9 | 17157 |
| 10 | 39087 |
| 11 | 78453 |
| 12 | 167183 |
| 13 | 344072 |
| 14 | 697116 |
| 15 | 1310344 |
| 16 | 2455274 |
| 17 | 4569557 |
| 18 | 7758203 |
| 19 | 13461761 |
| 20 | 23063807 |
| 21 | 39017035 |
| 22 | 66702580 |
| 23 | 106675941 |
| 24 | 172270944 |
| 25 | 274763136 |
| 26 | 437839603 |
| 27 | 693741098 |
| 28 | 1044076002 |
| 29 | 1596344378 |
| 30 | 2414009807 |
| 31 | 3653875720 |
[1,7,35,119,387,1050,2786,7160,17157,39087,78453, 167183,344072,697116,1310344,2455274,4569557, 7758203,13461761,23063807,39017035,66702580, 106675941,172270944,274763136,437839603,693741098, 1044076002,1596344378,2414009807,3653875720] |