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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 16 |
| 4 | 61 |
| 5 | 225 |
| 6 | 841 |
| 7 | 3136 |
| 8 | 11705 |
| 9 | 43681 |
| 10 | 163021 |
| 11 | 608400 |
| 12 | 2270581 |
| 13 | 8473921 |
| 14 | 31625105 |
| 15 | 118026496 |
| 16 | 440480881 |
| 17 | 1643897025 |
| 18 | 6135107221 |
| 19 | 22896531856 |
| 20 | 85451020205 |
| 21 | 318907548961 |
| 22 | 1190179175641 |
| 23 | 4441809153600 |
| 24 | 16577057438761 |
[1,5,16,61,225,841,3136,11705,43681,163021,608400, 2270581,8473921,31625105,118026496,440480881, 1643897025,6135107221,22896531856,85451020205, 318907548961,1190179175641,4441809153600, 16577057438761] |