heron:
SGF

heron:
It is not very helpful to just state that with no refutation. Can you show which moves I am missing?

heron:
D17 D19 E19 B19 C18 A18 does lead to ko. A18 B18 is still ko. The problem should not say no ko, current white resistance is wrong no?

Ivan Detkov:
Q3 Q1 P1 S1 R2 T2 - ko. The current state is OK

posetcay:
I think white can force a seki here with Q17-Q19, so we should probably mark seki solutions as correct.

AtariAnyone :
sorry in addition to my previous message this is of course assuming black starts with D3 and then white counters with D1. (bottom left orientation black to play)

AtariAnyone :
bottom left orientation if white starts with D1 we cannot avoid ko as far as i can see, this also matches with my cross-check on sensei library for Long L group with hane. sequence: D1 E1 B1 B2 C1 A3 A5

kovarex:
I changed the problem to be status based, and then it changed one of the varitations which was seki to be wrong (when there is other which is alive and alive is better then seki). Also, I added alternative white answer of the clamp, which is important to understand this problem and meaning of the hane, as without the hanne, it is 10 000 years ko, but with hane, this move doesn't work. (I added notes of it in respective variations). Let me know if I made a mistake.

posetcay:
After starting with R1, P1 instead of S2 kills.

todbeibrot:
and at the end black can play atri on the first line instead of hane. white is dead again

todbeibrot:
i think q17 is the right solution. q17 s19 q19 r18 s18 r19 t17 q17 s19 q19 r18 s18 t17 r19 and the stone on t16 comes into play r19 p19 and white is dead