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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 4 |
| 2 | 12 |
| 3 | 32 |
| 4 | 101 |
| 5 | 264 |
| 6 | 715 |
| 7 | 1624 |
| 8 | 3712 |
| 9 | 9726 |
| 10 | 21834 |
| 11 | 53792 |
| 12 | 128199 |
| 13 | 267188 |
| 14 | 539652 |
| 15 | 1153300 |
| 16 | 2579888 |
| 17 | 5149067 |
| 18 | 10688991 |
| 19 | 21413547 |
| 20 | 38696082 |
| 21 | 72239075 |
| 22 | 130346733 |
| 23 | 241575166 |
| 24 | 484716655 |
| 25 | 939025292 |
| 26 | 1666576578 |
| 27 | 2860265647 |
| 28 | 4508364585 |
| 29 | 6875274627 |
| 30 | 12911499333 |
| 31 | 23435167650 |
| 32 | 42980412215 |
[1,4,12,32,101,264,715,1624,3712,9726,21834,53792, 128199,267188,539652,1153300,2579888,5149067, 10688991,21413547,38696082,72239075,130346733, 241575166,484716655,939025292,1666576578, 2860265647,4508364585,6875274627,12911499333, 23435167650,42980412215] |