:
Without the second throw-in (as in the solution of Fujisawa Hideyuki, [LIT. 1; page 242]), the exchange of and secures Black an advantage of two points. It must be played now, because either a Black, or a White, move at 21 is absolute sente at any time.
776
:
secures Black an advantage of two points. It must be played now, because either a Black, or a White, move at 21 is absolute sente at any time.
