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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 4 |
| 4 | 19 |
| 5 | 31 |
| 6 | 70 |
| 7 | 117 |
| 8 | 253 |
| 9 | 538 |
| 10 | 1169 |
| 11 | 2401 |
| 12 | 4896 |
| 13 | 10179 |
| 14 | 21291 |
| 15 | 44754 |
| 16 | 93367 |
| 17 | 194747 |
| 18 | 405806 |
| 19 | 848007 |
| 20 | 1772209 |
| 21 | 3704016 |
| 22 | 7737207 |
| 23 | 16162351 |
| 24 | 33766226 |
| 25 | 70554991 |
| 26 | 147429719 |
| 27 | 308053298 |
| 28 | 643669403 |
| 29 | 1344939023 |
| 30 | 2810299720 |
| 31 | 5872263661 |
[1,3,4,19,31,70,117,253,538,1169,2401,4896,10179, 21291,44754,93367,194747,405806,848007,1772209, 3704016,7737207,16162351,33766226,70554991, 147429719,308053298,643669403,1344939023, 2810299720,5872263661] |