n | a(n) |
---|---|
0 | 1 |
1 | 6 |
2 | 15 |
3 | 70 |
4 | 325 |
5 | 1721 |
6 | 9449 |
7 | 54208 |
8 | 318943 |
9 | 1918427 |
10 | 11731931 |
11 | 72746099 |
12 | 456238871 |
13 | 2889149141 |
14 | 18447220199 |
15 | 118630723058 |
16 | 767675233277 |
17 | 4995186818805 |
18 | 32662752627705 |
19 | 214514289725729 |
20 | 1414397208516269 |
[1,6,15,70,325,1721,9449,54208,318943,1918427, 11731931,72746099,456238871,2889149141, 18447220199,118630723058,767675233277, 4995186818805,32662752627705,214514289725729, 1414397208516269] |