Compose a position December 31, 2009
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Today's puzzles were sent to us by Indian GM Sandipan Chanda.

Sandipan Chanda, 2009

White to play and win

Sandipan wrote of the the above position: "My engines take a long time to understand that it is winning for White. Moreover from the starting position they do not see it at all. This is strange, since there are many positions where engines do not understand perpetual check, stalemate, fortresses etc. But in my experience if there is a win then engines normally do not miss it." They do defend well, though, and so if you can win the position with white against your top engine you will probably have the solution. Incidentally the third move is usually the stumbling block.

The second problem is certainly one you have to solve on your own. Sandipan asks us to...

Compose a position where White has only a bare king and Black has king and three pawns (no double pawns). It is Black to play and the result is a draw.

Sandipan wrote: "Careful: some of my friends thought for a while and came up with triple pawns solution. No, they are not allowed either! I believe the problem has only one solution, with a minor dual and of course the mirrored positions. It does not 'tease' chess engines, but rather it is meant to stump chess friends who like to switch on their engines at the first opportunity. That does not help very much here."

We ran the position through our most powerful chess problem solving engine, GM John Nunn. He came up with the solution in twenty minutes – which means that it is very hard. We wish you luck in solving it.

Indian grandmaster Sandipan Chanda [photo Frits Agterdenbos]

For those of you who are still fresh and eager for more, here is an anti-computer problem that was submitted by Ed Zator, Toronto, Canada.

Vitaly Chekhover, Parna Ty Bull 1947

White to play and draw

It is very difficult – probably impossible – for computers to come up with the first two moves. If you work out the draw you may want to try your hand at a more elaborate version of the same basic idea:

F. Simkovitch, 3.hm L'Italia Scacchistica 1923

White to play and draw

Once again your only hope of finding the solution, we assume, is to play the position against the computer and come up with the insane second move that it will refuse to find.