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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 22 |
| 5 | 86 |
| 6 | 332 |
| 7 | 1217 |
| 8 | 4140 |
| 9 | 12934 |
| 10 | 37088 |
| 11 | 98115 |
| 12 | 241269 |
| 13 | 555881 |
| 14 | 1208988 |
| 15 | 2498732 |
| 16 | 4936275 |
| 17 | 9367783 |
| 18 | 17151454 |
| 19 | 30408684 |
| 20 | 52373368 |
| 21 | 87869112 |
| 22 | 143950884 |
| 23 | 230755459 |
| 24 | 362614022 |
| 25 | 559490596 |
| 26 | 848821676 |
| 27 | 1267845697 |
| 28 | 1866525871 |
| 29 | 2711186627 |
| 30 | 3889002516 |
| 31 | 5513499142 |
[1,2,6,22,86,332,1217,4140,12934,37088,98115, 241269,555881,1208988,2498732,4936275,9367783, 17151454,30408684,52373368,87869112,143950884, 230755459,362614022,559490596,848821676, 1267845697,1866525871,2711186627,3889002516, 5513499142] |