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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 15 |
| 3 | 66 |
| 4 | 201 |
| 5 | 469 |
| 6 | 958 |
| 7 | 1735 |
| 8 | 2937 |
| 9 | 4656 |
| 10 | 7050 |
| 11 | 10242 |
| 12 | 14461 |
| 13 | 19813 |
| 14 | 26569 |
| 15 | 34904 |
| 16 | 45086 |
| 17 | 57293 |
| 18 | 71898 |
| 19 | 89050 |
| 20 | 109201 |
| 21 | 132534 |
| 22 | 159424 |
| 23 | 190167 |
| 24 | 225296 |
| 25 | 264966 |
| 26 | 309685 |
| 27 | 359823 |
| 28 | 415889 |
| 29 | 478142 |
| 30 | 547302 |
| 31 | 623514 |
| 32 | 707593 |
| 33 | 799821 |
[0,1,15,66,201,469,958,1735,2937,4656,7050,10242, 14461,19813,26569,34904,45086,57293,71898,89050, 109201,132534,159424,190167,225296,264966,309685, 359823,415889,478142,547302,623514,707593,799821] |