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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 17 |
| 4 | 118 |
| 5 | 514 |
| 6 | 1681 |
| 7 | 4529 |
| 8 | 10612 |
| 9 | 22380 |
| 10 | 43473 |
| 11 | 79057 |
| 12 | 136202 |
| 13 | 224302 |
| 14 | 355537 |
| 15 | 545377 |
| 16 | 813128 |
| 17 | 1182520 |
| 18 | 1682337 |
| 19 | 2347089 |
| 20 | 3217726 |
| 21 | 4342394 |
| 22 | 5777233 |
| 23 | 7587217 |
| 24 | 9847036 |
| 25 | 12642020 |
| 26 | 16069105 |
| 27 | 20237841 |
| 28 | 25271442 |
| 29 | 31307878 |
| 30 | 38501009 |
| 31 | 47021761 |
[0,1,17,118,514,1681,4529,10612,22380,43473,79057, 136202,224302,355537,545377,813128,1182520, 1682337,2347089,3217726,4342394,5777233,7587217, 9847036,12642020,16069105,20237841,25271442, 31307878,38501009,47021761] |