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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 11 |
| 4 | 39 |
| 5 | 172 |
| 6 | 1163 |
| 7 | 6547 |
| 8 | 41772 |
| 9 | 335139 |
| 10 | 2486215 |
| 11 | 20078610 |
| 12 | 186139957 |
| 13 | 1676540257 |
| 14 | 16077206122 |
| 15 | 168739976555 |
| 16 | 1763716943267 |
| 17 | 19358116589964 |
| 18 | 226362412711759 |
| 19 | 2669223655597955 |
| 20 | 32748447519013132 |
| 21 | 421204995451111971 |
| 22 | 5496921281576148363 |
[1,1,2,11,39,172,1163,6547,41772,335139,2486215, 20078610,186139957,1676540257,16077206122, 168739976555,1763716943267,19358116589964, 226362412711759,2669223655597955, 32748447519013132,421204995451111971, 5496921281576148363] |