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| n | a(n) |
|---|---|
| 1 | 4 |
| 2 | 25 |
| 3 | 78 |
| 4 | 230 |
| 5 | 801 |
| 6 | 2764 |
| 7 | 9367 |
| 8 | 31703 |
| 9 | 107876 |
| 10 | 366903 |
| 11 | 1247178 |
| 12 | 4239444 |
| 13 | 14413593 |
| 14 | 49004114 |
| 15 | 166604979 |
| 16 | 566429535 |
| 17 | 1925785826 |
| 18 | 6547430725 |
| 19 | 22260469676 |
| 20 | 75682984684 |
| 21 | 257313518769 |
| 22 | 874837061986 |
| 23 | 2974348729093 |
| 24 | 10112457309015 |
[4,25,78,230,801,2764,9367,31703,107876,366903, 1247178,4239444,14413593,49004114,166604979, 566429535,1925785826,6547430725,22260469676, 75682984684,257313518769,874837061986, 2974348729093,10112457309015] |