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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 17 |
| 4 | 79 |
| 5 | 321 |
| 6 | 1497 |
| 7 | 6611 |
| 8 | 31267 |
| 9 | 142939 |
| 10 | 683295 |
| 11 | 3189011 |
| 12 | 15358587 |
| 13 | 72654977 |
| 14 | 351786797 |
| 15 | 1679905819 |
| 16 | 8166596697 |
| 17 | 39267480997 |
| 18 | 191484682817 |
| 19 | 925533860027 |
| 20 | 4524414195813 |
| 21 | 21957732601813 |
| 22 | 107554022372481 |
| 23 | 523676216690483 |
| 24 | 2569348152664739 |
| 25 | 12543177465406789 |
| 26 | 61627639102069263 |
| 27 | 301516113072994259 |
[1,1,5,17,79,321,1497,6611,31267,142939,683295, 3189011,15358587,72654977,351786797,1679905819, 8166596697,39267480997,191484682817,925533860027, 4524414195813,21957732601813,107554022372481, 523676216690483,2569348152664739, 12543177465406789,61627639102069263, 301516113072994259] |