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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 5 |
| 3 | 20 |
| 4 | 74 |
| 5 | 263 |
| 6 | 911 |
| 7 | 3098 |
| 8 | 10388 |
| 9 | 34445 |
| 10 | 113177 |
| 11 | 369056 |
| 12 | 1195742 |
| 13 | 3852947 |
| 14 | 12356003 |
| 15 | 39459494 |
| 16 | 125552936 |
| 17 | 398182169 |
| 18 | 1259116589 |
| 19 | 3971060012 |
| 20 | 12494310770 |
| 21 | 39226324511 |
| 22 | 122909150135 |
| 23 | 384417980210 |
| 24 | 1200325530044 |
| 25 | 3742191358373 |
| 26 | 11650218379841 |
| 27 | 36221588053688 |
| 28 | 112477562903558 |
| 29 | 348871084938155 |
[0,1,5,20,74,263,911,3098,10388,34445,113177, 369056,1195742,3852947,12356003,39459494, 125552936,398182169,1259116589,3971060012, 12494310770,39226324511,122909150135,384417980210, 1200325530044,3742191358373,11650218379841, 36221588053688,112477562903558,348871084938155] |