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| n | a(n) |
|---|---|
| 3 | 0 |
| 4 | 2 |
| 5 | 1 |
| 6 | 3 |
| 7 | 7 |
| 8 | 19 |
| 9 | 36 |
| 10 | 116 |
| 11 | 191 |
| 12 | 542 |
| 13 | 1204 |
| 14 | 3076 |
| 15 | 7560 |
| 16 | 18747 |
| 17 | 48658 |
| 18 | 123404 |
| 19 | 319762 |
| 20 | 834216 |
| 21 | 2150894 |
| 22 | 5618417 |
| 23 | 14633980 |
| 24 | 38301246 |
| 25 | 100457886 |
| 26 | 264025831 |
| 27 | 695595699 |
| 28 | 1836677008 |
| 29 | 4858965343 |
| 30 | 12883544605 |
| 31 | 34226273926 |
[0,2,1,3,7,19,36,116,191,542,1204,3076,7560,18747, 48658,123404,319762,834216,2150894,5618417, 14633980,38301246,100457886,264025831,695595699, 1836677008,4858965343,12883544605,34226273926] |