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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 2 |
| 3 | 5 |
| 4 | 5 |
| 5 | 17 |
| 6 | 37 |
| 7 | 101 |
| 8 | 197 |
| 9 | 401 |
| 10 | 677 |
| 11 | 1601 |
| 12 | 3137 |
| 13 | 8101 |
| 14 | 15877 |
| 15 | 32401 |
| 16 | 62501 |
| 17 | 122501 |
| 18 | 246017 |
| 19 | 512657 |
| 20 | 1020101 |
| 21 | 2073601 |
| 22 | 4137157 |
| 23 | 8386817 |
| 24 | 16695397 |
| 25 | 33339077 |
| 26 | 66977857 |
| 27 | 133772357 |
| 28 | 268304401 |
| 29 | 536663557 |
| 30 | 1073610757 |
| 31 | 2146098277 |
[2,2,5,5,17,37,101,197,401,677,1601,3137,8101, 15877,32401,62501,122501,246017,512657,1020101, 2073601,4137157,8386817,16695397,33339077, 66977857,133772357,268304401,536663557,1073610757, 2146098277] |