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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 10 |
| 3 | 25 |
| 4 | 68 |
| 5 | 208 |
| 6 | 609 |
| 7 | 1785 |
| 8 | 5375 |
| 9 | 16174 |
| 10 | 48589 |
| 11 | 146652 |
| 12 | 443220 |
| 13 | 1339225 |
| 14 | 4049457 |
| 15 | 12250187 |
| 16 | 37060306 |
| 17 | 112130705 |
| 18 | 339304900 |
| 19 | 1026763976 |
| 20 | 3107142321 |
| 21 | 9402919993 |
| 22 | 28455721175 |
| 23 | 86115053750 |
| 24 | 260609950693 |
| 25 | 788686494268 |
| 26 | 2386813930604 |
[3,10,25,68,208,609,1785,5375,16174,48589,146652, 443220,1339225,4049457,12250187,37060306, 112130705,339304900,1026763976,3107142321, 9402919993,28455721175,86115053750,260609950693, 788686494268,2386813930604] |