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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 259 |
| 3 | 496 |
| 4 | 1203 |
| 5 | 2596 |
| 6 | 3939 |
| 7 | 8020 |
| 8 | 16119 |
| 9 | 23940 |
| 10 | 47719 |
| 11 | 94920 |
| 12 | 140503 |
| 13 | 279096 |
| 14 | 554203 |
| 15 | 819880 |
| 16 | 1627659 |
| 17 | 3231100 |
| 18 | 4779579 |
| 19 | 9487660 |
| 20 | 18833199 |
| 21 | 27858396 |
| 22 | 55299103 |
| 23 | 109768896 |
| 24 | 162371599 |
| 25 | 322307760 |
| 26 | 639780979 |
| 27 | 946372000 |
| 28 | 1878548259 |
| 29 | 3728917780 |
| 30 | 5515861203 |
[0,259,496,1203,2596,3939,8020,16119,23940,47719, 94920,140503,279096,554203,819880,1627659,3231100, 4779579,9487660,18833199,27858396,55299103, 109768896,162371599,322307760,639780979,946372000, 1878548259,3728917780,5515861203] |