Thursday, December 31, 2009

The twelve puzzles of Christmas


Ellerman, 1951

White to play and mate in two moves

7 comments:

Anonymous said...

This was difficult. White has several plausible tries which only just fail.

1.Nd6 (threat 2.Nb7 mate).
1...cxd6 2.Bb6 mate.
1...exd6 2.Rxc7 mate.
1...Qxd6 2.Qc1 mate.
1...Kxd6 2.Qxe7 mate.

James

Lauri said...

What happens if Rxe7 threatening either Qc1 or Rxc7?

Tom Chivers said...

I think this is the first two mover I've ever gotten! My method was a lucky guess.

Have a good NYE everyone!

Anonymous said...

1Rxe7 would fail to ...Qf4. Happy New Year to all!

PG

Anonymous said...

Lauri. After 1.Rxe7, Black can play the non-committal ...h4 since White doesn't have a mate. 2.Rxc7+ Qc6 and 2.Qc1+ Qxc1+ are not mates in two.

One of the few things I know about problems is that the first move is never a capture or a check.

James

ejh said...

I admit I don't know that much about modern conventions in these things, but am I right in thinking that captures and checks are considered acceptable as first moves in studies, but not currently in problems?

ejh said...

By the way, 1.Nd6 is indeed correct, and the puzzle was taken from Hooper and Whyld, The Oxford Companion To Chess, OUP 1984.

They mention that there are:

...four set play mates (what would happen if Black were to move first):

1...c6 2.Bb6
1...e6 2.Rxc7
1...g6 2.Qxe7
1...g5 2.Qc1

The key is 1.Nd6, threatening Nb7, and in four main variations the mating moves of the set play recur, preceded by 'changed' black moves:

1...cxd6 2.Bb6
1...exd6 2.Rxc7
1...Kxd6 2.Qxe7
1...Qxd6 2.Qc1.