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| n | a(n) |
|---|---|
| 1 | 4 |
| 2 | 13 |
| 3 | 42 |
| 4 | 131 |
| 5 | 398 |
| 6 | 1186 |
| 7 | 3482 |
| 8 | 10103 |
| 9 | 29034 |
| 10 | 82777 |
| 11 | 234424 |
| 12 | 660098 |
| 13 | 1849552 |
| 14 | 5160001 |
| 15 | 14341098 |
| 16 | 39723791 |
| 17 | 109701122 |
| 18 | 302131618 |
| 19 | 830079014 |
| 20 | 2275509227 |
| 21 | 6225274794 |
| 22 | 16999389733 |
| 23 | 46341292012 |
| 24 | 126130604546 |
| 25 | 342800478748 |
| 26 | 930414584821 |
| 27 | 2522124577962 |
| 28 | 6828859302683 |
[4,13,42,131,398,1186,3482,10103,29034,82777, 234424,660098,1849552,5160001,14341098,39723791, 109701122,302131618,830079014,2275509227, 6225274794,16999389733,46341292012,126130604546, 342800478748,930414584821,2522124577962, 6828859302683] |