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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 5 |
| 6 | 10 |
| 7 | 17 |
| 8 | 27 |
| 9 | 46 |
| 10 | 86 |
| 11 | 165 |
| 12 | 308 |
| 13 | 558 |
| 14 | 1006 |
| 15 | 1841 |
| 16 | 3421 |
| 17 | 6383 |
| 18 | 11863 |
| 19 | 21966 |
| 20 | 40697 |
| 21 | 75662 |
| 22 | 141099 |
| 23 | 263429 |
| 24 | 491778 |
| 25 | 918104 |
| 26 | 1715259 |
| 27 | 3208078 |
| 28 | 6005818 |
| 29 | 11250198 |
| 30 | 21082487 |
| 31 | 39524241 |
| 32 | 74135187 |
| 33 | 139128897 |
| 34 | 261228200 |
| 35 | 490682127 |
| 36 | 922015964 |
| 37 | 1733127107 |
| 38 | 3258939997 |
| 39 | 6130162494 |
| 40 | 11534742080 |
[1,1,1,1,2,5,10,17,27,46,86,165,308,558,1006,1841, 3421,6383,11863,21966,40697,75662,141099,263429, 491778,918104,1715259,3208078,6005818,11250198, 21082487,39524241,74135187,139128897,261228200, 490682127,922015964,1733127107,3258939997, 6130162494,11534742080] |