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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 11 |
| 5 | 18 |
| 6 | 116 |
| 7 | 157 |
| 8 | 1110 |
| 9 | 3076 |
| 10 | 21808 |
| 11 | 42335 |
| 12 | 528612 |
| 13 | 859502 |
| 14 | 8547036 |
| 15 | 31968397 |
| 16 | 159716545 |
| 17 | 398048506 |
| 18 | 5303680564 |
| 19 | 8835749347 |
| 20 | 99411986634 |
| 21 | 331215914028 |
| 22 | 1987084129352 |
| 23 | 4515860983385 |
| 24 | 62095481040014 |
[1,2,4,11,18,116,157,1110,3076,21808,42335,528612, 859502,8547036,31968397,159716545,398048506, 5303680564,8835749347,99411986634,331215914028, 1987084129352,4515860983385,62095481040014] |