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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 4 |
| 3 | 10 |
| 4 | 21 |
| 5 | 39 |
| 6 | 66 |
| 7 | 104 |
| 8 | 155 |
| 9 | 221 |
| 10 | 304 |
| 11 | 406 |
| 12 | 529 |
| 13 | 675 |
| 14 | 846 |
| 15 | 1044 |
| 16 | 1271 |
| 17 | 1529 |
| 18 | 1820 |
| 19 | 2146 |
| 20 | 2509 |
| 21 | 2911 |
| 22 | 3354 |
| 23 | 3840 |
| 24 | 4371 |
| 25 | 4949 |
| 26 | 5576 |
| 27 | 6254 |
| 28 | 6985 |
| 29 | 7771 |
| 30 | 8614 |
| 31 | 9516 |
| 32 | 10479 |
| 33 | 11505 |
| 34 | 12596 |
| 35 | 13754 |
| 36 | 14981 |
| 37 | 16279 |
| 38 | 17650 |
| 39 | 19096 |
| 40 | 20619 |
| 41 | 22221 |
[1,4,10,21,39,66,104,155,221,304,406,529,675,846, 1044,1271,1529,1820,2146,2509,2911,3354,3840,4371, 4949,5576,6254,6985,7771,8614,9516,10479,11505, 12596,13754,14981,16279,17650,19096,20619,22221] |