Can You Find the Best Constant for Sum-Free Subsets?

[Joffan]

I probably won't produce any more explicit sets after this, but just for something more to chew on,
B={1,2,3,4,5,6,8,10,12,15,16,18,20,24,25,30,32,36,40,48,50,60,64,80} has maximal sum-free subset size of 10, giving a new upper bound on c ≤ 10/24 = 5/12

 

[mfb]

@Joffan: See post #29 for the constant.

 

[Joffan]

@Joffan: See post #29 for the constant.

I was deliberately ignoring post#29 as it uses outside knowledge.

I thought real data sets might also help to restart the thought processes of those of us still interested in solving it and perhaps serve as test cases. A bit of groping around blindly perhaps, but that can occasionally turn up something interesting.