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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 1 |
| 8 | 2 |
| 9 | 9 |
| 10 | 37 |
| 11 | 121 |
| 12 | 331 |
| 13 | 793 |
| 14 | 1717 |
| 15 | 3433 |
| 16 | 6436 |
| 17 | 11441 |
| 18 | 19449 |
| 19 | 31825 |
| 20 | 50389 |
| 21 | 77521 |
| 22 | 116281 |
| 23 | 170545 |
| 24 | 245158 |
| 25 | 346105 |
| 26 | 480701 |
| 27 | 657802 |
| 28 | 888058 |
| 29 | 1184419 |
| 30 | 1564435 |
| 31 | 2063206 |
| 32 | 2799487 |
| 33 | 4272049 |
| 34 | 8544097 |
| 35 | 23535821 |
| 36 | 77331981 |
| 37 | 262534537 |
| 38 | 865287625 |
| 39 | 2720095405 |
[1,1,1,1,1,1,1,1,2,9,37,121,331,793,1717,3433, 6436,11441,19449,31825,50389,77521,116281,170545, 245158,346105,480701,657802,888058,1184419, 1564435,2063206,2799487,4272049,8544097,23535821, 77331981,262534537,865287625,2720095405] |