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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 1 |
| 3 | 7 |
| 4 | 17 |
| 5 | 55 |
| 6 | 17 |
| 7 | 119 |
| 8 | 273 |
| 9 | 887 |
| 10 | 273 |
| 11 | 1911 |
| 12 | 4369 |
| 13 | 14199 |
| 14 | 4369 |
| 15 | 30583 |
| 16 | 69905 |
| 17 | 227191 |
| 18 | 69905 |
| 19 | 489335 |
| 20 | 1118481 |
| 21 | 3635063 |
| 22 | 1118481 |
| 23 | 7829367 |
| 24 | 17895697 |
| 25 | 58161015 |
| 26 | 17895697 |
| 27 | 125269879 |
| 28 | 286331153 |
| 29 | 930576247 |
| 30 | 286331153 |
| 31 | 2004318071 |
| 32 | 4581298449 |
| 33 | 14889219959 |
[1,3,1,7,17,55,17,119,273,887,273,1911,4369,14199, 4369,30583,69905,227191,69905,489335,1118481, 3635063,1118481,7829367,17895697,58161015, 17895697,125269879,286331153,930576247,286331153, 2004318071,4581298449,14889219959] |