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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 4 |
| 2 | 10 |
| 3 | 24 |
| 4 | 54 |
| 5 | 118 |
| 6 | 252 |
| 7 | 530 |
| 8 | 1102 |
| 9 | 2272 |
| 10 | 4654 |
| 11 | 9486 |
| 12 | 19260 |
| 13 | 38986 |
| 14 | 78726 |
| 15 | 158672 |
| 16 | 319318 |
| 17 | 641830 |
| 18 | 1288828 |
| 19 | 2586018 |
| 20 | 5185566 |
| 21 | 10393024 |
| 22 | 20821470 |
| 23 | 41700254 |
| 24 | 83493244 |
| 25 | 167136538 |
| 26 | 334515862 |
| 27 | 669424560 |
| 28 | 1339484742 |
| 29 | 2679997942 |
| 30 | 5361659964 |
| 31 | 10726012466 |
| 32 | 21456381550 |
[1,4,10,24,54,118,252,530,1102,2272,4654,9486, 19260,38986,78726,158672,319318,641830,1288828, 2586018,5185566,10393024,20821470,41700254, 83493244,167136538,334515862,669424560,1339484742, 2679997942,5361659964,10726012466,21456381550] |