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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 14 |
| 4 | 46 |
| 5 | 144 |
| 6 | 540 |
| 7 | 1952 |
| 8 | 7066 |
| 9 | 27326 |
| 10 | 104192 |
| 11 | 402370 |
| 12 | 1583626 |
| 13 | 6253532 |
| 14 | 24935669 |
| 15 | 99650433 |
| 16 | 402653095 |
| 17 | 1634611082 |
| 18 | 6627794165 |
| 19 | 27175594747 |
| 20 | 111655473179 |
| 21 | 458521078228 |
| 22 | 1898047857400 |
| 23 | 7871222083602 |
| 24 | 32657227815791 |
| 25 | 136120126645941 |
| 26 | 568766898128386 |
| 27 | 2378607344430242 |
| 28 | 9970920272017160 |
[1,2,4,14,46,144,540,1952,7066,27326,104192, 402370,1583626,6253532,24935669,99650433, 402653095,1634611082,6627794165,27175594747, 111655473179,458521078228,1898047857400, 7871222083602,32657227815791,136120126645941, 568766898128386,2378607344430242,9970920272017160] |