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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 1 |
| 5 | 2 |
| 6 | 5 |
| 7 | 9 |
| 8 | 18 |
| 9 | 36 |
| 10 | 73 |
| 11 | 145 |
| 12 | 290 |
| 13 | 580 |
| 14 | 1159 |
| 15 | 2319 |
| 16 | 4637 |
| 17 | 9273 |
| 18 | 18544 |
| 19 | 37083 |
| 20 | 74157 |
| 21 | 148330 |
| 22 | 296658 |
| 23 | 593311 |
| 24 | 1186613 |
| 25 | 2373208 |
| 26 | 4746380 |
| 27 | 9492687 |
| 28 | 18985447 |
| 29 | 37970821 |
| 30 | 75941497 |
| 31 | 151882704 |
| 32 | 303764828 |
| 33 | 607528497 |
| 34 | 1215054675 |
| 35 | 2430104713 |
| 36 | 4860217541 |
[0,0,1,1,2,5,9,18,36,73,145,290,580,1159,2319, 4637,9273,18544,37083,74157,148330,296658,593311, 1186613,2373208,4746380,9492687,18985447,37970821, 75941497,151882704,303764828,607528497,1215054675, 2430104713,4860217541] |