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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 4 |
| 3 | 97 |
| 4 | 1064 |
| 5 | 32289 |
| 6 | 598380 |
| 7 | 22574145 |
| 8 | 593534160 |
| 9 | 26957380545 |
| 10 | 920377787220 |
| 11 | 48996867845025 |
| 12 | 2059752490500600 |
| 13 | 125880489657907425 |
| 14 | 6289366704447815100 |
| 15 | 434143177716332484225 |
| 16 | 25139306218115649924000 |
| 17 | 1934812150723967345546625 |
| 18 | 127427485507344478670350500 |
[1,4,97,1064,32289,598380,22574145,593534160, 26957380545,920377787220,48996867845025, 2059752490500600,125880489657907425, 6289366704447815100,434143177716332484225, 25139306218115649924000,1934812150723967345546625, 127427485507344478670350500] |