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| n | a(n) |
|---|---|
| 0 | 3 |
| 1 | 6 |
| 2 | 11 |
| 3 | 20 |
| 4 | 36 |
| 5 | 64 |
| 6 | 113 |
| 7 | 199 |
| 8 | 350 |
| 9 | 615 |
| 10 | 1080 |
| 11 | 1896 |
| 12 | 3328 |
| 13 | 5841 |
| 14 | 10251 |
| 15 | 17990 |
| 16 | 31571 |
| 17 | 55404 |
| 18 | 97228 |
| 19 | 170624 |
| 20 | 299425 |
| 21 | 525455 |
| 22 | 922110 |
| 23 | 1618191 |
| 24 | 2839728 |
| 25 | 4983376 |
| 26 | 8745216 |
| 27 | 15346785 |
| 28 | 26931731 |
| 29 | 47261894 |
| 30 | 82938843 |
| 31 | 145547524 |
| 32 | 255418100 |
| 33 | 448227520 |
| 34 | 786584465 |
[3,6,11,20,36,64,113,199,350,615,1080,1896,3328, 5841,10251,17990,31571,55404,97228,170624,299425, 525455,922110,1618191,2839728,4983376,8745216, 15346785,26931731,47261894,82938843,145547524, 255418100,448227520,786584465] |