On 2015-09-12 00:30, Bill Gosper wrote:

Iff Sum[a[k]-a[2k-1]-a[2k]] -> 0. True? Named? --rwg False: Exercise: Construct a divergent sum(a(k)) with sum(a(k)-a(2k)-a(2k-1)) = 0. Named? Simpson's Rule. (Homer's) --rwg Harder: if a[k]:=1/k/log(k) then Sum(k>1)[a[k]-a[2k-1]-a[2k]] = 1/Log[4].