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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 5 |
| 5 | 9 |
| 6 | 27 |
| 7 | 46 |
| 8 | 145 |
| 9 | 244 |
| 10 | 796 |
| 11 | 1330 |
| 12 | 4438 |
| 13 | 7382 |
| 14 | 25034 |
| 15 | 41508 |
| 16 | 142479 |
| 17 | 235672 |
| 18 | 816620 |
| 19 | 1348204 |
| 20 | 4706977 |
| 21 | 7759105 |
| 22 | 27256963 |
| 23 | 44873972 |
| 24 | 158450461 |
| 25 | 260581699 |
| 26 | 924129535 |
| 27 | 1518390034 |
| 28 | 5404960900 |
| 29 | 8873524820 |
| 30 | 31689099660 |
| 31 | 51988770150 |
[1,1,1,2,5,9,27,46,145,244,796,1330,4438,7382, 25034,41508,142479,235672,816620,1348204,4706977, 7759105,27256963,44873972,158450461,260581699, 924129535,1518390034,5404960900,8873524820, 31689099660,51988770150] |