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| n | a(n) |
|---|---|
| 1 | 20 |
| 2 | 90 |
| 3 | 272 |
| 4 | 468 |
| 5 | 650 |
| 6 | 1332 |
| 7 | 2900 |
| 8 | 3600 |
| 9 | 2450 |
| 10 | 7650 |
| 11 | 4160 |
| 12 | 6642 |
| 13 | 10388 |
| 14 | 16400 |
| 15 | 10100 |
| 16 | 25578 |
| 17 | 14762 |
| 18 | 27540 |
| 19 | 20880 |
| 20 | 42048 |
| 21 | 50960 |
| 22 | 54900 |
| 23 | 28730 |
| 24 | 90650 |
| 25 | 60500 |
| 26 | 38612 |
| 27 | 98100 |
| 28 | 50850 |
| 29 | 125712 |
| 30 | 142400 |
| 31 | 149940 |
| 32 | 65792 |
| 33 | 141570 |
| 34 | 116948 |
| 35 | 214650 |
| 36 | 83810 |
| 37 | 105300 |
| 38 | 265232 |
| 39 | 354368 |
[20,90,272,468,650,1332,2900,3600,2450,7650,4160, 6642,10388,16400,10100,25578,14762,27540,20880, 42048,50960,54900,28730,90650,60500,38612,98100, 50850,125712,142400,149940,65792,141570,116948, 214650,83810,105300,265232,354368] |