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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 10 |
| 6 | 29 |
| 7 | 101 |
| 8 | 367 |
| 9 | 1562 |
| 10 | 6891 |
| 11 | 37871 |
| 12 | 197930 |
| 13 | 1121634 |
| 14 | 6888085 |
| 15 | 46190282 |
| 16 | 323250987 |
| 17 | 2349020516 |
| 18 | 17897285514 |
| 19 | 142512956148 |
| 20 | 1178963284732 |
| 21 | 10248806222398 |
| 22 | 91421283039658 |
| 23 | 847666112839362 |
| 24 | 8100455404172267 |
| 25 | 79925567946537362 |
| 26 | 814508927747776069 |
[1,1,1,2,4,10,29,101,367,1562,6891,37871,197930, 1121634,6888085,46190282,323250987,2349020516, 17897285514,142512956148,1178963284732, 10248806222398,91421283039658,847666112839362, 8100455404172267,79925567946537362, 814508927747776069] |