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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 30 |
| 3 | 434 |
| 4 | 3740 |
| 5 | 22220 |
| 6 | 100562 |
| 7 | 370909 |
| 8 | 1168008 |
| 9 | 3245311 |
| 10 | 8148590 |
| 11 | 18821968 |
| 12 | 40542228 |
| 13 | 82300842 |
| 14 | 158779362 |
| 15 | 293092635 |
| 16 | 520505744 |
| 17 | 893364637 |
| 18 | 1487517086 |
| 19 | 2410539918 |
| 20 | 3812130380 |
| 21 | 5897064040 |
| 22 | 8941168786 |
| 23 | 13310814265 |
| 24 | 19486468504 |
| 25 | 28090928475 |
| 26 | 39922889006 |
[0,1,30,434,3740,22220,100562,370909,1168008, 3245311,8148590,18821968,40542228,82300842, 158779362,293092635,520505744,893364637, 1487517086,2410539918,3812130380,5897064040, 8941168786,13310814265,19486468504,28090928475, 39922889006] |