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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 16 |
| 4 | 60 |
| 5 | 254 |
| 6 | 1199 |
| 7 | 6206 |
| 8 | 34827 |
| 9 | 210264 |
| 10 | 1355992 |
| 11 | 9288954 |
| 12 | 67279309 |
| 13 | 513149498 |
| 14 | 4107383185 |
| 15 | 34398823888 |
| 16 | 300629113292 |
| 17 | 2735356900806 |
| 18 | 25857446103571 |
| 19 | 253472859754918 |
| 20 | 2572266378189583 |
| 21 | 26981781750668760 |
| 22 | 292136508070103208 |
| 23 | 3260640536587635410 |
| 24 | 37472102225288489529 |
[1,2,5,16,60,254,1199,6206,34827,210264,1355992, 9288954,67279309,513149498,4107383185,34398823888, 300629113292,2735356900806,25857446103571, 253472859754918,2572266378189583, 26981781750668760,292136508070103208, 3260640536587635410,37472102225288489529] |