(;SZ[19]AW[ma]AW[mb]AW[rb]AW[mc]AW[md]AW[qd]AW[me]AB[na]AB[oa]AB[pa]AB[qa]AB[ra]AB[sa]AB[sb]AB[nc]AB[oc]AB[pc]AB[qc]AB[rc]AB[sc]AB[sd]AB[ne]AB[oe]AB[pe]AB[qe]AB[re]AB[se]LB[nb:A]LB[nd:B]C[White to play. Remember there are other endgame moves on the board, keeping sente has value to both players.]GM[1]FF[4]CA[UTF-8]AP[CGoban:2]ST[2]RU[Japanese]KM[0.00]PW[White]PB[Black]PL[W] (;W[nb]C[White gets 1 point in sente (if Black defends at P18), 2 points in gote (if white tenukies first but defends if White continues at P18), 3 points in double gote (if White responds to Q18) or 5 points in quadruple gote (if White does not respond at all). So for White to tenuki is less costly than in the other path, hence B is better.]) (;W[nd]C[Correct. Compared to Black defending at O16 at the end of the game White gets 1 point in sente (if Black defends at P16), 2 points in gote (if white tenukies first but defends if White continues at P16) or 5 points in triple gote (if White does not respond at all). Taking sente costs White more than in the other path.RIGHT]))