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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 23 |
| 4 | 61 |
| 5 | 421 |
| 6 | 1103 |
| 7 | 7563 |
| 8 | 19801 |
| 9 | 135721 |
| 10 | 355323 |
| 11 | 2435423 |
| 12 | 6376021 |
| 13 | 43701901 |
| 14 | 114413063 |
| 15 | 784198803 |
| 16 | 2053059121 |
| 17 | 14071876561 |
| 18 | 36840651123 |
| 19 | 252509579303 |
| 20 | 661078661101 |
| 21 | 4531100550901 |
| 22 | 11862575248703 |
| 23 | 81307300336923 |
| 24 | 212865275815561 |
| 25 | 1459000305513721 |
[1,3,23,61,421,1103,7563,19801,135721,355323, 2435423,6376021,43701901,114413063,784198803, 2053059121,14071876561,36840651123,252509579303, 661078661101,4531100550901,11862575248703, 81307300336923,212865275815561,1459000305513721] |