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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 181 |
| 4 | 931 |
| 5 | 3001 |
| 6 | 7621 |
| 7 | 16621 |
| 8 | 32551 |
| 9 | 58801 |
| 10 | 99721 |
| 11 | 160741 |
| 12 | 248491 |
| 13 | 370921 |
| 14 | 537421 |
| 15 | 758941 |
| 16 | 1048111 |
| 17 | 1419361 |
| 18 | 1889041 |
| 19 | 2475541 |
| 20 | 3199411 |
| 21 | 4083481 |
| 22 | 5152981 |
| 23 | 6435661 |
| 24 | 7961911 |
| 25 | 9764881 |
| 26 | 11880601 |
| 27 | 14348101 |
| 28 | 17209531 |
| 29 | 20510281 |
| 30 | 24299101 |
[1,1,181,931,3001,7621,16621,32551,58801,99721, 160741,248491,370921,537421,758941,1048111, 1419361,1889041,2475541,3199411,4083481,5152981, 6435661,7961911,9764881,11880601,14348101, 17209531,20510281,24299101] |