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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 7 |
| 7 | 43 |
| 8 | 169 |
| 9 | 505 |
| 10 | 1261 |
| 11 | 4159 |
| 12 | 38809 |
| 13 | 334621 |
| 14 | 2036035 |
| 15 | 9489481 |
| 16 | 38390353 |
| 17 | 257371297 |
| 18 | 3131783929 |
| 19 | 32230292725 |
| 20 | 246760346161 |
| 21 | 1493969858641 |
| 22 | 9196517088991 |
| 23 | 101815213853431 |
| 24 | 1450104259874425 |
| 25 | 16645720979718601 |
| 26 | 147298665834676357 |
[1,1,1,1,1,1,7,43,169,505,1261,4159,38809,334621, 2036035,9489481,38390353,257371297,3131783929, 32230292725,246760346161,1493969858641, 9196517088991,101815213853431,1450104259874425, 16645720979718601,147298665834676357] |