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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 11 |
| 5 | 25 |
| 6 | 59 |
| 7 | 142 |
| 8 | 335 |
| 9 | 796 |
| 10 | 1892 |
| 11 | 4489 |
| 12 | 10661 |
| 13 | 25315 |
| 14 | 60104 |
| 15 | 142717 |
| 16 | 338870 |
| 17 | 804616 |
| 18 | 1910507 |
| 19 | 4536349 |
| 20 | 10771211 |
| 21 | 25575430 |
| 22 | 60726899 |
| 23 | 144191392 |
| 24 | 342371480 |
| 25 | 812934961 |
| 26 | 1930252097 |
| 27 | 4583236459 |
| 28 | 10882545536 |
| 29 | 25839774745 |
| 30 | 61354575194 |
[0,1,2,4,11,25,59,142,335,796,1892,4489,10661, 25315,60104,142717,338870,804616,1910507,4536349, 10771211,25575430,60726899,144191392,342371480, 812934961,1930252097,4583236459,10882545536, 25839774745,61354575194] |