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| n | a(n) |
|---|---|
| 1 | 4 |
| 2 | 12 |
| 3 | 42 |
| 4 | 106 |
| 5 | 300 |
| 6 | 654 |
| 7 | 1664 |
| 8 | 3300 |
| 9 | 7940 |
| 10 | 15018 |
| 11 | 34948 |
| 12 | 64396 |
| 13 | 147130 |
| 14 | 267404 |
| 15 | 604722 |
| 16 | 1090998 |
| 17 | 2453492 |
| 18 | 4409000 |
| 19 | 9886266 |
| 20 | 17729222 |
| 21 | 39693612 |
| 22 | 71108358 |
| 23 | 159076784 |
| 24 | 284820632 |
| 25 | 636918540 |
| 26 | 1140064414 |
| 27 | 2548902598 |
| 28 | 4561828606 |
| 29 | 10198077780 |
| 30 | 18250461694 |
| 31 | 40797250536 |
| 32 | 73008145904 |
| 33 | 163198882506 |
| 34 | 292045189424 |
| 35 | 652815291522 |
[4,12,42,106,300,654,1664,3300,7940,15018,34948, 64396,147130,267404,604722,1090998,2453492, 4409000,9886266,17729222,39693612,71108358, 159076784,284820632,636918540,1140064414, 2548902598,4561828606,10198077780,18250461694, 40797250536,73008145904,163198882506,292045189424, 652815291522] |