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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 7 |
| 4 | 11 |
| 5 | 32 |
| 6 | 154 |
| 7 | 319 |
| 8 | 1184 |
| 9 | 7084 |
| 10 | 17864 |
| 11 | 79328 |
| 12 | 559636 |
| 13 | 1643488 |
| 14 | 8408768 |
| 15 | 67715956 |
| 16 | 225157856 |
| 17 | 1294950272 |
| 18 | 11647144432 |
| 19 | 43005150496 |
| 20 | 273234507392 |
| 21 | 2702137508224 |
| 22 | 10923308225984 |
| 23 | 75685958547584 |
| 24 | 813343389975424 |
| 25 | 3560998481670784 |
| 26 | 26641457408749568 |
[1,1,2,7,11,32,154,319,1184,7084,17864,79328, 559636,1643488,8408768,67715956,225157856, 1294950272,11647144432,43005150496,273234507392, 2702137508224,10923308225984,75685958547584, 813343389975424,3560998481670784, 26641457408749568] |