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| n | a(n) |
|---|---|
| 0 | 4 |
| 1 | 37 |
| 2 | 190 |
| 3 | 715 |
| 4 | 2200 |
| 5 | 5863 |
| 6 | 14014 |
| 7 | 30745 |
| 8 | 62920 |
| 9 | 121550 |
| 10 | 223652 |
| 11 | 394706 |
| 12 | 671840 |
| 13 | 1107890 |
| 14 | 1776500 |
| 15 | 2778446 |
| 16 | 4249388 |
| 17 | 6369275 |
| 18 | 9373650 |
| 19 | 13567125 |
| 20 | 19339320 |
| 21 | 27183585 |
| 22 | 37718850 |
| 23 | 51714975 |
| 24 | 70122000 |
| 25 | 94103724 |
| 26 | 125076072 |
| 27 | 164750740 |
[4,37,190,715,2200,5863,14014,30745,62920,121550, 223652,394706,671840,1107890,1776500,2778446, 4249388,6369275,9373650,13567125,19339320, 27183585,37718850,51714975,70122000,94103724, 125076072,164750740] |