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| n | a(n) |
|---|---|
| 0 | 4 |
| 1 | 11 |
| 2 | 37 |
| 3 | 122 |
| 4 | 403 |
| 5 | 1331 |
| 6 | 4396 |
| 7 | 14519 |
| 8 | 47953 |
| 9 | 158378 |
| 10 | 523087 |
| 11 | 1727639 |
| 12 | 5706004 |
| 13 | 18845651 |
| 14 | 62242957 |
| 15 | 205574522 |
| 16 | 678966523 |
| 17 | 2242474091 |
| 18 | 7406388796 |
| 19 | 24461640479 |
| 20 | 80791310233 |
| 21 | 266835571178 |
| 22 | 881298023767 |
| 23 | 2910729642479 |
| 24 | 9613486951204 |
| 25 | 31751190496091 |
| 26 | 104867058439477 |
| 27 | 346352365814522 |
[4,11,37,122,403,1331,4396,14519,47953,158378, 523087,1727639,5706004,18845651,62242957, 205574522,678966523,2242474091,7406388796, 24461640479,80791310233,266835571178,881298023767, 2910729642479,9613486951204,31751190496091, 104867058439477,346352365814522] |