f n
= 2 :
[4, 6 .. m
] where m
= if even n
then n
else n
- 1
main
= mapM_ p
[0, 1, 2, 3, 4, 5, 6, 7]
ZiBuID0gMiA6IFs0LCA2IC4uIG1dIHdoZXJlIG0gPSBpZiBldmVuIG4gdGhlbiBuIGVsc2UgbiAtIDEKZyBuID0gMiA6IGZpbHRlciBldmVuIFszLi5uXQoKcCBuID0gcHV0U3RyTG4gJCBzaG93IG4gKysgIiA9ICIgKysgc2hvdyAoZiBuKSArKyAiID0gIiArKyBzaG93IChnIG4pCgptYWluID0gbWFwTV8gcCBbMCwgMSwgMiwgMywgNCwgNSwgNiwgN10=
0 = [2] = [2]
1 = [2] = [2]
2 = [2] = [2]
3 = [2] = [2]
4 = [2,4] = [2,4]
5 = [2,4] = [2,4]
6 = [2,4,6] = [2,4,6]
7 = [2,4,6] = [2,4,6]