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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 10 |
| 3 | 46 |
| 4 | 226 |
| 5 | 1136 |
| 6 | 5810 |
| 7 | 30080 |
| 8 | 157162 |
| 9 | 826992 |
| 10 | 4376408 |
| 11 | 23267332 |
| 12 | 124179570 |
| 13 | 664919780 |
| 14 | 3570265000 |
| 15 | 19216805476 |
| 16 | 103652442922 |
| 17 | 560127574340 |
| 18 | 3031887311256 |
| 19 | 16435458039076 |
| 20 | 89213101943000 |
| 21 | 484839755040768 |
| 22 | 2637805800869740 |
| 23 | 14365506336197816 |
[1,2,10,46,226,1136,5810,30080,157162,826992, 4376408,23267332,124179570,664919780,3570265000, 19216805476,103652442922,560127574340, 3031887311256,16435458039076,89213101943000, 484839755040768,2637805800869740, 14365506336197816] |