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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 4 |
| 3 | 13 |
| 4 | 59 |
| 5 | 151 |
| 6 | 916 |
| 7 | 1961 |
| 8 | 12035 |
| 9 | 35110 |
| 10 | 166204 |
| 11 | 384781 |
| 12 | 3154367 |
| 13 | 5600323 |
| 14 | 34384676 |
| 15 | 124093963 |
| 16 | 582290595 |
| 17 | 1235438587 |
| 18 | 9831378712 |
| 19 | 18602770421 |
| 20 | 144738772109 |
| 21 | 410101237013 |
| 22 | 1721535323380 |
| 23 | 4295702988313 |
| 24 | 40309503022439 |
[1,4,13,59,151,916,1961,12035,35110,166204,384781, 3154367,5600323,34384676,124093963,582290595, 1235438587,9831378712,18602770421,144738772109, 410101237013,1721535323380,4295702988313, 40309503022439] |