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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 7 |
| 4 | 28 |
| 5 | 76 |
| 6 | 166 |
| 7 | 316 |
| 8 | 547 |
| 9 | 883 |
| 10 | 1351 |
| 11 | 1981 |
| 12 | 2806 |
| 13 | 3862 |
| 14 | 5188 |
| 15 | 6826 |
| 16 | 8821 |
| 17 | 11221 |
| 18 | 14077 |
| 19 | 17443 |
| 20 | 21376 |
| 21 | 25936 |
| 22 | 31186 |
| 23 | 37192 |
| 24 | 44023 |
| 25 | 51751 |
| 26 | 60451 |
| 27 | 70201 |
| 28 | 81082 |
| 29 | 93178 |
| 30 | 106576 |
| 31 | 121366 |
| 32 | 137641 |
| 33 | 155497 |
| 34 | 175033 |
| 35 | 196351 |
| 36 | 219556 |
| 37 | 244756 |
| 38 | 272062 |
| 39 | 301588 |
[0,1,7,28,76,166,316,547,883,1351,1981,2806,3862, 5188,6826,8821,11221,14077,17443,21376,25936, 31186,37192,44023,51751,60451,70201,81082,93178, 106576,121366,137641,155497,175033,196351,219556, 244756,272062,301588] |