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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 23 |
| 3 | 83 |
| 4 | 464 |
| 5 | 2280 |
| 6 | 11423 |
| 7 | 57453 |
| 8 | 288496 |
| 9 | 1447883 |
| 10 | 7274348 |
| 11 | 36527122 |
| 12 | 183441729 |
| 13 | 921291768 |
| 14 | 4626743261 |
| 15 | 23236097303 |
| 16 | 116694404423 |
| 17 | 586051094416 |
| 18 | 2943215292116 |
| 19 | 14781150469720 |
| 20 | 74232557467951 |
| 21 | 372804116464754 |
[1,23,83,464,2280,11423,57453,288496,1447883, 7274348,36527122,183441729,921291768,4626743261, 23236097303,116694404423,586051094416, 2943215292116,14781150469720,74232557467951, 372804116464754] |