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| n | a(n) |
|---|---|
| 1 | 21 |
| 2 | 65 |
| 3 | 158 |
| 4 | 331 |
| 5 | 626 |
| 6 | 1098 |
| 7 | 1817 |
| 8 | 2871 |
| 9 | 4367 |
| 10 | 6435 |
| 11 | 9230 |
| 12 | 12935 |
| 13 | 17764 |
| 14 | 23965 |
| 15 | 31824 |
| 16 | 41667 |
| 17 | 53865 |
| 18 | 68837 |
| 19 | 87054 |
| 20 | 109043 |
| 21 | 135391 |
| 22 | 166750 |
| 23 | 203840 |
| 24 | 247455 |
| 25 | 298467 |
| 26 | 357831 |
| 27 | 426590 |
| 28 | 505880 |
| 29 | 596936 |
| 30 | 701096 |
| 31 | 819808 |
| 32 | 954635 |
| 33 | 1107261 |
[21,65,158,331,626,1098,1817,2871,4367,6435,9230, 12935,17764,23965,31824,41667,53865,68837,87054, 109043,135391,166750,203840,247455,298467,357831, 426590,505880,596936,701096,819808,954635,1107261] |