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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 8 |
| 3 | 49 |
| 4 | 246 |
| 5 | 1157 |
| 6 | 5248 |
| 7 | 23256 |
| 8 | 101398 |
| 9 | 436865 |
| 10 | 1865136 |
| 11 | 7906054 |
| 12 | 33319388 |
| 13 | 139754994 |
| 14 | 583859968 |
| 15 | 2430991670 |
| 16 | 10092510630 |
| 17 | 41794856985 |
| 18 | 172699266480 |
| 19 | 712220712390 |
| 20 | 2932169392020 |
| 21 | 12052941519030 |
| 22 | 49475929052160 |
| 23 | 202838118604680 |
[1,1,8,49,246,1157,5248,23256,101398,436865, 1865136,7906054,33319388,139754994,583859968, 2430991670,10092510630,41794856985,172699266480, 712220712390,2932169392020,12052941519030, 49475929052160,202838118604680] |