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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 1 |
| 5 | 2 |
| 6 | 4 |
| 7 | 8 |
| 8 | 15 |
| 9 | 29 |
| 10 | 56 |
| 11 | 108 |
| 12 | 208 |
| 13 | 401 |
| 14 | 773 |
| 15 | 1490 |
| 16 | 2872 |
| 17 | 5536 |
| 18 | 10671 |
| 19 | 20569 |
| 20 | 39648 |
| 21 | 76424 |
| 22 | 147312 |
| 23 | 283953 |
| 24 | 547337 |
| 25 | 1055026 |
| 26 | 2033628 |
| 27 | 3919944 |
| 28 | 7555935 |
| 29 | 14564533 |
| 30 | 28074040 |
| 31 | 54114452 |
| 32 | 104308960 |
| 33 | 201061985 |
| 34 | 387559437 |
| 35 | 747044834 |
| 36 | 1439975216 |
| 37 | 2775641472 |
[0,0,0,1,1,2,4,8,15,29,56,108,208,401,773,1490, 2872,5536,10671,20569,39648,76424,147312,283953, 547337,1055026,2033628,3919944,7555935,14564533, 28074040,54114452,104308960,201061985,387559437, 747044834,1439975216,2775641472] |