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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 3 |
| 3 | 7 |
| 4 | 16 |
| 5 | 44 |
| 6 | 124 |
| 7 | 388 |
| 8 | 1256 |
| 9 | 4360 |
| 10 | 15664 |
| 11 | 59264 |
| 12 | 231568 |
| 13 | 942736 |
| 14 | 3953120 |
| 15 | 17151424 |
| 16 | 76448224 |
| 17 | 350871008 |
| 18 | 1650490816 |
| 19 | 7966168960 |
| 20 | 39325494464 |
| 21 | 198648873664 |
| 22 | 1024484257408 |
| 23 | 5394759478016 |
| 24 | 28957897398400 |
[1,2,3,7,16,44,124,388,1256,4360,15664,59264, 231568,942736,3953120,17151424,76448224,350871008, 1650490816,7966168960,39325494464,198648873664, 1024484257408,5394759478016,28957897398400] |