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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 13 |
| 5 | 25 |
| 6 | 63 |
| 7 | 103 |
| 8 | 193 |
| 9 | 489 |
| 10 | 835 |
| 11 | 1647 |
| 12 | 4061 |
| 13 | 6545 |
| 14 | 12543 |
| 15 | 31343 |
| 16 | 53505 |
| 17 | 105073 |
| 18 | 258307 |
| 19 | 424567 |
| 20 | 790797 |
| 21 | 2005641 |
| 22 | 3420447 |
| 23 | 6748855 |
| 24 | 16634209 |
| 25 | 26811769 |
| 26 | 51377059 |
| 27 | 128377535 |
| 28 | 219165917 |
| 29 | 430383937 |
| 30 | 1058044767 |
| 31 | 1739056639 |
[1,3,7,13,25,63,103,193,489,835,1647,4061,6545, 12543,31343,53505,105073,258307,424567,790797, 2005641,3420447,6748855,16634209,26811769, 51377059,128377535,219165917,430383937,1058044767, 1739056639] |