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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 21 |
| 5 | 70 |
| 6 | 203 |
| 7 | 517 |
| 8 | 1187 |
| 9 | 2504 |
| 10 | 4921 |
| 11 | 9107 |
| 12 | 16009 |
| 13 | 26922 |
| 14 | 43567 |
| 15 | 68177 |
| 16 | 103591 |
| 17 | 153356 |
| 18 | 221837 |
| 19 | 314335 |
| 20 | 437213 |
| 21 | 598030 |
| 22 | 805683 |
| 23 | 1070557 |
| 24 | 1404683 |
| 25 | 1821904 |
| 26 | 2338049 |
| 27 | 2971115 |
| 28 | 3741457 |
| 29 | 4671986 |
| 30 | 5788375 |
| 31 | 7119273 |
| 32 | 8696527 |
| 33 | 10555412 |
| 34 | 12734869 |
| 35 | 15277751 |
[1,2,6,21,70,203,517,1187,2504,4921,9107,16009, 26922,43567,68177,103591,153356,221837,314335, 437213,598030,805683,1070557,1404683,1821904, 2338049,2971115,3741457,4671986,5788375,7119273, 8696527,10555412,12734869,15277751] |