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| n | a(n) |
|---|---|
| 1 | 60 |
| 2 | 210 |
| 3 | 1716 |
| 4 | 5814 |
| 5 | 26970 |
| 6 | 74046 |
| 7 | 215940 |
| 8 | 373176 |
| 9 | 1061106 |
| 10 | 1259604 |
| 11 | 2627934 |
| 12 | 3374850 |
| 13 | 5831820 |
| 14 | 7077696 |
| 15 | 7762194 |
| 16 | 11852124 |
| 17 | 13823760 |
| 18 | 19682730 |
| 19 | 22425486 |
| 20 | 30371016 |
| 21 | 42143844 |
| 22 | 74087580 |
| 23 | 80621136 |
| 24 | 98610666 |
| 25 | 142236126 |
| 26 | 185192430 |
[60,210,1716,5814,26970,74046,215940,373176, 1061106,1259604,2627934,3374850,5831820,7077696, 7762194,11852124,13823760,19682730,22425486, 30371016,42143844,74087580,80621136,98610666, 142236126,185192430] |