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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 3 |
| 5 | 4 |
| 6 | 6 |
| 7 | 13 |
| 8 | 31 |
| 9 | 72 |
| 10 | 142 |
| 11 | 255 |
| 12 | 465 |
| 13 | 868 |
| 14 | 1666 |
| 15 | 3361 |
| 16 | 7099 |
| 17 | 15430 |
| 18 | 34044 |
| 19 | 75547 |
| 20 | 167389 |
| 21 | 367849 |
| 22 | 797275 |
| 23 | 1698682 |
| 24 | 3557446 |
| 25 | 7341014 |
| 26 | 14981954 |
| 27 | 30363966 |
| 28 | 61351570 |
| 29 | 123962309 |
| 30 | 250941549 |
| 31 | 509475411 |
| 32 | 1038043409 |
| 33 | 2123698576 |
| 34 | 4365471714 |
| 35 | 9022527237 |
| 36 | 18760483331 |
| 37 | 39258381744 |
[1,1,1,3,4,6,13,31,72,142,255,465,868,1666,3361, 7099,15430,34044,75547,167389,367849,797275, 1698682,3557446,7341014,14981954,30363966, 61351570,123962309,250941549,509475411,1038043409, 2123698576,4365471714,9022527237,18760483331, 39258381744] |