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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 4 |
| 3 | 12 |
| 4 | 35 |
| 5 | 84 |
| 6 | 209 |
| 7 | 450 |
| 8 | 990 |
| 9 | 2010 |
| 10 | 4074 |
| 11 | 7784 |
| 12 | 15015 |
| 13 | 27472 |
| 14 | 50355 |
| 15 | 89408 |
| 16 | 158004 |
| 17 | 271755 |
| 18 | 466620 |
| 19 | 782530 |
| 20 | 1308549 |
| 21 | 2149488 |
| 22 | 3513012 |
| 23 | 5657540 |
| 24 | 9076725 |
| 25 | 14367804 |
| 26 | 22645056 |
| 27 | 35313320 |
| 28 | 54810756 |
| 29 | 84269900 |
| 30 | 129032100 |
| 31 | 195879618 |
| 32 | 296147379 |
| 33 | 444466260 |
| 34 | 664284530 |
| 35 | 986341059 |
| 36 | 1458941412 |
[1,4,12,35,84,209,450,990,2010,4074,7784,15015, 27472,50355,89408,158004,271755,466620,782530, 1308549,2149488,3513012,5657540,9076725,14367804, 22645056,35313320,54810756,84269900,129032100, 195879618,296147379,444466260,664284530,986341059, 1458941412] |