19 Jun 06
Originally posted by TuranthorOkay. Here's a puzzle:
KP up 2 would be e5? if he was Black I guess!
My "who moves their King 2ce in the first 3 moves" was in reply to Tommy C's comical notation accomodating this "new mate".
Black can checkmate white on the second move in eight ways.
1.f4 d6 2.g5 Qh4#
1.g5 d6 2.f4 Qh4#
1.f3 d6 2.g5 Qh4#
1.g5 d6 2.f3 Qh4#
1.f4 d5 2.g5 Qh4#
1.g5 d5 2.f4 Qh4#
1.f3 d5 2.g5 Qh4#
1.g5 d5 2.f3 Qh4#
How many ways can white checkmate black on the third move?
19 Jun 06
Originally posted by WulebgrHow can white start with 1. g5?
Okay. Here's a puzzle:
Black can checkmate white on the second move in eight ways.
1.f4 d6 2.g5 Qh4#
1.g5 d6 2.f4 Qh4#
1.f3 d6 2.g5 Qh4#
1.g5 d6 2.f3 Qh4#
1.f4 d5 2.g5 Qh4#
1.g5 d5 2.f4 Qh4#
1.f3 d5 2.g5 Qh4#
1.g5 d5 2.f3 Qh4#
How many ways can white checkmate black on the third move?
19 Jun 06
Originally posted by TommyCClever misreading. 😛
None, since he just got mated the move before.
Let me rephrase the question. How many possible sequences of moves from the starting position lead to white delivering checkmate on move 3?
Here's one:
1.a3 f6 2.e3 g5 3.Qh5#
Originally posted by Wulebgr
Insert g4 everywhere I typed g5. My error, sorry. It was late at night when I posted.
Now, answer the question (if you can).
d5 and d6 also should be e5 and e6. Aaargh! I should verify before I post game scores.
19 Jun 06
2 edits
Originally posted by WulebgrI can't find any 3-move mate other than the reversed fool's mate.
Okay. Here's a puzzle:
Black can checkmate white on the second move in eight ways.
1.f4 d6 2.g5 Qh4#
1.g5 d6 2.f4 Qh4#
1.f3 d6 2.g5 Qh4#
1.g5 d6 2.f3 Qh4#
1.f4 d5 2.g5 Qh4#
1.g5 d5 2.f4 Qh4#
1.f3 d5 2.g5 Qh4#
1.g5 d5 2.f3 Qh4#
How many ways can white checkmate black on the third move?
The number of 'reversed fool's mates' ( i.e., black pawns on f5/f6 and g5, with 3.Qh5# ) seems to be 304. (This problem is fairly complicated and I wouldn't be surprised if I've missed something...)
Black has four different move orders to play out his f- and g-pawns.
White can start by moving the e-pawn, or not moving the e-pawn.
1.Not moving e-pawn: (18 first moves - 3 that block Q diagonal) * 2 different 2nd moves = 30
2.Moving the e-pawn: 2 first moves * (the 15 moves from case 1 plus 7 Q/B moves that don't spoil the mate + 1 for a new mate: Be2-h5) = 46
Add 1 and 2: 76
Multiply by the 4 Black permutations: 304
19 Jun 06
1 edit
Originally posted by BigDoggProblemThank you. So, 304 appears to be the correct answer.
I can't find any other 3-move mate other than the reversed fool's mate.
The number of 'reversed fool's mates' ( i.e., black pawns on f5/f6 and g5, with 3.Qh5# ) seems to be [b]304. (This problem is fairly complicated and I wouldn't be surprised if I've missed something...)
Black has four different move orders to play out his f- and g-pawns. ...[text shortened]... r a new mate: Be2-h5) = 46
Add 1 and 2: 76
Multiply by the 4 Black permutations: 304[/b]
I've given this problem to a number of people over the past few years, sometimes telling them that the answer was a bit over 290 but that I hadn't taken the time to work out the exact number. Your is the first answer that has come back.
Addendum: So, now when someone brags of knowing a four-move checkmate, we can ask how many versions of Fool's mate they know. We've established 312, but there are many more. Black can mate white on move 3 (instead of two) how many ways?