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| n | a(n) |
|---|---|
| 1 | 10 |
| 2 | 30 |
| 3 | 100 |
| 4 | 330 |
| 5 | 1100 |
| 6 | 3670 |
| 7 | 12230 |
| 8 | 40770 |
| 9 | 135900 |
| 10 | 453000 |
| 11 | 1510000 |
| 12 | 5033330 |
| 13 | 16777770 |
| 14 | 55925900 |
| 15 | 186419660 |
| 16 | 621398870 |
| 17 | 2071329570 |
| 18 | 6904431900 |
| 19 | 23014773000 |
| 20 | 76715910000 |
| 21 | 255719700000 |
| 22 | 852399000000 |
| 23 | 2841330000000 |
| 24 | 9471100000000 |
| 25 | 31570333333330 |
| 26 | 105234444444430 |
[10,30,100,330,1100,3670,12230,40770,135900, 453000,1510000,5033330,16777770,55925900, 186419660,621398870,2071329570,6904431900, 23014773000,76715910000,255719700000,852399000000, 2841330000000,9471100000000,31570333333330, 105234444444430] |