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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 497 |
| 3 | 19603 |
| 4 | 254449 |
| 5 | 1952501 |
| 6 | 9742691 |
| 7 | 40351207 |
| 8 | 130277873 |
| 9 | 385845769 |
| 10 | 970392997 |
| 11 | 2357933051 |
| 12 | 4987963747 |
| 13 | 10604470813 |
| 14 | 20054549879 |
| 15 | 38274877103 |
| 16 | 66702270961 |
| 17 | 118587792977 |
| 18 | 191765347193 |
| 19 | 322687567459 |
| 20 | 496811926949 |
| 21 | 791004710821 |
| 22 | 1171892726347 |
| 23 | 1801152381623 |
[1,497,19603,254449,1952501,9742691,40351207, 130277873,385845769,970392997,2357933051, 4987963747,10604470813,20054549879,38274877103, 66702270961,118587792977,191765347193, 322687567459,496811926949,791004710821, 1171892726347,1801152381623] |