“…Furthermore, there is not a single graph with c 2 = −z 3 or −z 4 whose period is known. What we do have is the conjectured period of two completed primitive graphs at loop order 7 (graphs P 7,8 and P 7,9 in [20]) with c 2 -invariant −z 2 . They are weight 11 multiple zeta values, namely [4] To summarize the results for quasi-constant graphs, the 10 loop data are consistent with the following, rather surprising, conjecture.…”