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| n | a(n) |
|---|---|
| 1 | 6 |
| 2 | 48 |
| 3 | 222 |
| 4 | 840 |
| 5 | 2922 |
| 6 | 9816 |
| 7 | 32268 |
| 8 | 103920 |
| 9 | 327972 |
| 10 | 1016604 |
| 11 | 3104886 |
| 12 | 9372384 |
| 13 | 28021722 |
| 14 | 83102064 |
| 15 | 244684278 |
| 16 | 715869972 |
| 17 | 2082493224 |
| 18 | 6027558060 |
| 19 | 17367361116 |
| 20 | 49839214272 |
| 21 | 142499394102 |
| 22 | 406078307556 |
| 23 | 1153665098214 |
| 24 | 3268423142640 |
| 25 | 9235877073966 |
| 26 | 26036948624628 |
| 27 | 73239840519138 |
| 28 | 205599420581796 |
| 29 | 576065888328156 |
[6,48,222,840,2922,9816,32268,103920,327972, 1016604,3104886,9372384,28021722,83102064, 244684278,715869972,2082493224,6027558060, 17367361116,49839214272,142499394102,406078307556, 1153665098214,3268423142640,9235877073966, 26036948624628,73239840519138,205599420581796, 576065888328156] |