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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 4 |
| 3 | 10 |
| 4 | 21 |
| 5 | 39 |
| 6 | 70 |
| 7 | 120 |
| 8 | 205 |
| 9 | 342 |
| 10 | 568 |
| 11 | 924 |
| 12 | 1490 |
| 13 | 2356 |
| 14 | 3684 |
| 15 | 5666 |
| 16 | 8619 |
| 17 | 12935 |
| 18 | 19230 |
| 19 | 28280 |
| 20 | 41260 |
| 21 | 59680 |
| 22 | 85740 |
| 23 | 122306 |
| 24 | 173447 |
| 25 | 244472 |
| 26 | 342774 |
| 27 | 478014 |
| 28 | 663391 |
| 29 | 916149 |
| 30 | 1259526 |
| 31 | 1723772 |
| 32 | 2349209 |
| 33 | 3188160 |
| 34 | 4309660 |
| 35 | 5803002 |
| 36 | 7785040 |
| 37 | 10406296 |
| 38 | 13862404 |
[1,1,4,10,21,39,70,120,205,342,568,924,1490,2356, 3684,5666,8619,12935,19230,28280,41260,59680, 85740,122306,173447,244472,342774,478014,663391, 916149,1259526,1723772,2349209,3188160,4309660, 5803002,7785040,10406296,13862404] |