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| n | a(n) |
|---|---|
| 1 | 12 |
| 2 | 28 |
| 3 | 27 |
| 4 | 136 |
| 5 | 301 |
| 6 | 899 |
| 7 | 2922 |
| 8 | 7680 |
| 9 | 24326 |
| 10 | 71539 |
| 11 | 213378 |
| 12 | 637327 |
| 13 | 1919823 |
| 14 | 5779272 |
| 15 | 17262590 |
| 16 | 52036278 |
| 17 | 156828887 |
| 18 | 470650712 |
| 19 | 1416414013 |
| 20 | 4267310387 |
| 21 | 12839872102 |
| 22 | 38624812870 |
| 23 | 116319554088 |
| 24 | 350228413447 |
| 25 | 1053958512376 |
[12,28,27,136,301,899,2922,7680,24326,71539, 213378,637327,1919823,5779272,17262590,52036278, 156828887,470650712,1416414013,4267310387, 12839872102,38624812870,116319554088,350228413447, 1053958512376] |