Sadaharu:
Playing S2 instead of T2 as the first move should give the same result. S2 T4 T2

todbeibrot:
SGF

todbeibrot:
t4 q2 p2 s2 r3 and white is alive. after t4 black should start with s2. if white answers at s1, t2 threatens r3. and if white plays r3 he doesnt have enough room to live after p2. t2 r3 t4 should have a variation. now the q2 idea seems to work. so q2 p2 s2 q1 t5 white is dead. and q2 p2 s2 s1 r1 t3 leads to ko.