[Retros] FEN fun

[Joost de Heer]

Eric,

1. a4 2. Ra2 3. Sa3 (2 possible orders)
1. a4 2. Ra2 3. Sc3 (3 possible orders)

All orders have no last pawn move.

The same thing can be done on the f/h file too. So that's 10 different
sequences. Black has the same, so in total there are 100 possibilities.

Joost

On Tue, July 30, 2013 15:46, Eric Angelini wrote:

> This is it !

> (told you, 5-minute puzzle !-)

> ... and 16 solutions with this "trick" p+N+R

> Best,

> É.

>

>

> -----Message d'origine-----

> De : retros-bounces at janko.at [mailto:retros-bounces at janko.at] De la part

> de Joost de Heer

> Envoyé : mardi 30 juillet 2013 14:21

> À : The Retrograde Analysis Mailing List

> Cc : alexandre.wajnberg at skynet.be

> Objet : Re: [Retros] FEN fun

>

> On Tue, July 30, 2013 10:47, Eric Angelini wrote:

>>

>> Hello Retro-fans,

>> here is a 5-minute puzzle for the August break.

>>

>> It is possible to reach, after Black's third move,

>> many positions having a FEN format where all numbers are prime.

>> Find a game where the last move was _not_ a pawn move.

>> (The solution is far from being unique -- but the "trick" yes,

>> I hope.)

>>

>> http://en.wikipedia.org/wiki/Forsyth%E2%80%93Edwards_Notation

>

> Hello Eric,

>

> I can't really see a trick, so either I'm missing something or there is a

> different solution which does use a trick:

>

> 1. h4 h5 2. Rh2 Rh7 3. Sh3 Sh6

> rsbqkb2/pppppppr/7s/7p/7P/7S/PPPPPPPR/RSBQKB2

>

> Joost

> _______________________________________________

> Retros mailing list

> Retros at janko.at

> http://www.pairlist.net/mailman/listinfo/retros

>