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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 5 |
| 2 | 13 |
| 3 | 141 |
| 4 | 653 |
| 5 | 1677 |
| 6 | 3725 |
| 7 | 20109 |
| 8 | 544397 |
| 9 | 2641549 |
| 10 | 6835853 |
| 11 | 15224461 |
| 12 | 32001677 |
| 13 | 65556109 |
| 14 | 132664973 |
| 15 | 266882701 |
| 16 | 803753613 |
| 17 | 1877495437 |
| 18 | 4024979085 |
| 19 | 8319946381 |
| 20 | 16909880973 |
| 21 | 51269619341 |
| 22 | 601025433229 |
| 23 | 1700537061005 |
[1,5,13,141,653,1677,3725,20109,544397,2641549, 6835853,15224461,32001677,65556109,132664973, 266882701,803753613,1877495437,4024979085, 8319946381,16909880973,51269619341,601025433229, 1700537061005] |