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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 8 |
| 3 | 32 |
| 4 | 140 |
| 5 | 617 |
| 6 | 2825 |
| 7 | 12989 |
| 8 | 60799 |
| 9 | 285605 |
| 10 | 1355212 |
| 11 | 6448778 |
| 12 | 30876524 |
| 13 | 148182226 |
| 14 | 714046275 |
| 15 | 3447484841 |
| 16 | 16691884243 |
| 17 | 80949584877 |
| 18 | 393388278159 |
| 19 | 1914344878230 |
| 20 | 9330462585841 |
| 21 | 45528694065925 |
| 22 | 222436937930322 |
| 23 | 1087807926738612 |
| 24 | 5325191050098931 |
| 25 | 26090385582013999 |
| 26 | 127934831995426037 |
[1,2,8,32,140,617,2825,12989,60799,285605,1355212, 6448778,30876524,148182226,714046275,3447484841, 16691884243,80949584877,393388278159, 1914344878230,9330462585841,45528694065925, 222436937930322,1087807926738612,5325191050098931, 26090385582013999,127934831995426037] |