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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 7 |
| 3 | 28 |
| 4 | 117 |
| 5 | 511 |
| 6 | 2291 |
| 7 | 10463 |
| 8 | 48435 |
| 9 | 226586 |
| 10 | 1068587 |
| 11 | 5072224 |
| 12 | 24203714 |
| 13 | 115998071 |
| 14 | 557962305 |
| 15 | 2692152543 |
| 16 | 13023978409 |
| 17 | 63151137877 |
| 18 | 306820781473 |
| 19 | 1493308343577 |
| 20 | 7279262948313 |
| 21 | 35532416043118 |
| 22 | 173659581034563 |
| 23 | 849680918961093 |
| 24 | 4161500769723001 |
| 25 | 20400516021424974 |
| 26 | 100090905058019708 |
[1,2,7,28,117,511,2291,10463,48435,226586,1068587, 5072224,24203714,115998071,557962305,2692152543, 13023978409,63151137877,306820781473, 1493308343577,7279262948313,35532416043118, 173659581034563,849680918961093,4161500769723001, 20400516021424974,100090905058019708] |