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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 7 |
| 5 | 12 |
| 6 | 20 |
| 7 | 33 |
| 8 | 72 |
| 9 | 196 |
| 10 | 710 |
| 11 | 1546 |
| 12 | 2599 |
| 13 | 6738 |
| 14 | 19553 |
| 15 | 80688 |
| 16 | 185625 |
| 17 | 978142 |
| 18 | 2432840 |
| 19 | 12112678 |
| 20 | 29466988 |
| 21 | 39202128 |
| 22 | 40962878 |
| 23 | 41948928 |
| 24 | 42570288 |
| 25 | 42684103 |
| 26 | 43265540 |
| 27 | 44518036 |
| 28 | 52194742 |
| 29 | 65214030 |
| 30 | 159581828 |
| 31 | 337649208 |
[0,1,2,4,7,12,20,33,72,196,710,1546,2599,6738, 19553,80688,185625,978142,2432840,12112678, 29466988,39202128,40962878,41948928,42570288, 42684103,43265540,44518036,52194742,65214030, 159581828,337649208] |