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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 5 |
| 3 | 40 |
| 4 | 207 |
| 5 | 778 |
| 6 | 2199 |
| 7 | 5126 |
| 8 | 10501 |
| 9 | 19630 |
| 10 | 34274 |
| 11 | 56754 |
| 12 | 90071 |
| 13 | 138042 |
| 14 | 205453 |
| 15 | 298230 |
| 16 | 423629 |
| 17 | 590446 |
| 18 | 809248 |
| 19 | 1092626 |
| 20 | 1455471 |
| 21 | 1915274 |
| 22 | 2492451 |
| 23 | 3210694 |
| 24 | 4097349 |
| 25 | 5183822 |
| 26 | 6506014 |
| 27 | 8104786 |
| 28 | 10026455 |
| 29 | 12323322 |
| 30 | 15054233 |
| 31 | 18285174 |
[2,5,40,207,778,2199,5126,10501,19630,34274,56754, 90071,138042,205453,298230,423629,590446,809248, 1092626,1455471,1915274,2492451,3210694,4097349, 5183822,6506014,8104786,10026455,12323322, 15054233,18285174] |