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| n | a(n) |
|---|---|
| 1 | 4 |
| 2 | 28 |
| 3 | 136 |
| 4 | 1216 |
| 5 | 1216 |
| 6 | 16768 |
| 7 | 203392 |
| 8 | 1043200 |
| 9 | 6082048 |
| 10 | 36315136 |
| 11 | 36315136 |
| 12 | 1487503360 |
| 13 | 1487503360 |
| 14 | 1487503360 |
| 15 | 314944159744 |
| 16 | 785129144320 |
| 17 | 12069568774144 |
| 18 | 45922887663616 |
| 19 | 452162714337280 |
| 20 | 2280241934368768 |
| 21 | 2280241934368768 |
| 22 | 2280241934368768 |
| 23 | 2280241934368768 |
[4,28,136,1216,1216,16768,203392,1043200,6082048, 36315136,36315136,1487503360,1487503360, 1487503360,314944159744,785129144320, 12069568774144,45922887663616,452162714337280, 2280241934368768,2280241934368768, 2280241934368768,2280241934368768] |