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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 6 |
| 3 | 4 |
| 4 | 19 |
| 5 | 32 |
| 6 | 72 |
| 7 | 164 |
| 8 | 331 |
| 9 | 790 |
| 10 | 1700 |
| 11 | 3879 |
| 12 | 8689 |
| 13 | 19763 |
| 14 | 44787 |
| 15 | 101708 |
| 16 | 232136 |
| 17 | 528496 |
| 18 | 1206975 |
| 19 | 2755982 |
| 20 | 6298876 |
| 21 | 14399412 |
| 22 | 32932776 |
| 23 | 75341117 |
| 24 | 172383450 |
| 25 | 394513860 |
| 26 | 902958422 |
| 27 | 2066919648 |
| 28 | 4731632878 |
| 29 | 10832452949 |
| 30 | 24800620478 |
[1,6,4,19,32,72,164,331,790,1700,3879,8689,19763, 44787,101708,232136,528496,1206975,2755982, 6298876,14399412,32932776,75341117,172383450, 394513860,902958422,2066919648,4731632878, 10832452949,24800620478] |