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| n | a(n) |
|---|---|
| 1 | 7 |
| 2 | 20 |
| 3 | 53 |
| 4 | 147 |
| 5 | 401 |
| 6 | 1105 |
| 7 | 3034 |
| 8 | 8349 |
| 9 | 22957 |
| 10 | 63155 |
| 11 | 173711 |
| 12 | 477852 |
| 13 | 1314449 |
| 14 | 3615799 |
| 15 | 9946297 |
| 16 | 27360297 |
| 17 | 75262642 |
| 18 | 207032537 |
| 19 | 569505065 |
| 20 | 1566594819 |
| 21 | 4309389479 |
| 22 | 11854270468 |
| 23 | 32608731853 |
| 24 | 89700113451 |
| 25 | 246747109345 |
| 26 | 678752052689 |
| 27 | 1867111432010 |
| 28 | 5136050915445 |
[7,20,53,147,401,1105,3034,8349,22957,63155, 173711,477852,1314449,3615799,9946297,27360297, 75262642,207032537,569505065,1566594819, 4309389479,11854270468,32608731853,89700113451, 246747109345,678752052689,1867111432010, 5136050915445] |