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| n | a(n) |
|---|---|
| 1 | 268 |
| 2 | 628 |
| 3 | 1116 |
| 4 | 3336 |
| 5 | 6364 |
| 6 | 22748 |
| 7 | 44540 |
| 8 | 178572 |
| 9 | 353428 |
| 10 | 1512256 |
| 11 | 3007252 |
| 12 | 13311628 |
| 13 | 26527148 |
| 14 | 119439828 |
| 15 | 238241724 |
| 16 | 1081829832 |
| 17 | 2158800908 |
| 18 | 9844644828 |
| 19 | 19648912012 |
| 20 | 89797542908 |
| 21 | 179243095124 |
| 22 | 820073869984 |
| 23 | 1637003801252 |
[268,628,1116,3336,6364,22748,44540,178572,353428, 1512256,3007252,13311628,26527148,119439828, 238241724,1081829832,2158800908,9844644828, 19648912012,89797542908,179243095124,820073869984, 1637003801252] |