% Francois Labelle & computer, January 24, 2004 % All 41 at home PG-4.5 with exactly 1 solution. % They are all SPGs. (Forsyth-Edwards Notation, followed by the same list in ascii diagrams) SPG-4.5: rnbqkb1r/pppppppp/8/8/8/8/PPPP1PPP/1NBQKBNR rn1qkbnr/ppp1pppp/8/8/8/8/1PPPPPPP/1NBQKBNR rn1qkbnr/pp2pppp/8/8/8/8/PPPPPPPP/R1BQKBNR r1bqkbnr/pppppppp/8/8/8/8/PPP2PPP/R1BQKBNR rnb1kbnr/pppp1ppp/8/8/8/8/PPPPPP1P/R1BQKBNR rnb1kbnr/pppp1ppp/8/8/8/8/PPPPPPP1/R1BQKBNR rnb1kbnr/ppp1pppp/8/8/8/8/PPPP1P1P/R1BQKBNR rnb1kbnr/ppp1pppp/8/8/8/8/PPPPPP1P/R1BQKBN1 rnb1kbnr/ppp1pppp/8/8/8/8/PP1PPP1P/RNBQKBN1 rnbqk1nr/pppp1ppp/8/8/8/8/PPPPPPPP/RNBQKB1R rnbqk1nr/pppp2pp/8/8/8/8/PPPPPPPP/RNBQKB1R rnbqkb1r/pppppppp/8/8/8/8/PPP2PPP/RNBQKB1R r1bqkbnr/pppppppp/8/8/8/8/PPPP1PPP/RNBQKB1R rnb1kbnr/pppp1ppp/8/8/8/8/P1PPPPPP/RNBQKB1R rnbqkbnr/ppppppp1/8/8/8/8/PPPP1PPP/RNBQKBNR rnbqkbnr/pppppp1p/8/8/8/8/PPPP1PPP/RNBQKBNR rnbqkbnr/p1pppppp/8/8/8/8/PPPP1PPP/RNBQKBNR r1bqkbnr/pppppppp/8/8/8/8/PPP1P1PP/RNBQKBNR rnbqkbnr/ppppppp1/8/8/8/8/PPP1PPPP/RNBQKBNR rnbqkbnr/pppppp1p/8/8/8/8/PPP1PPPP/RNBQKBNR r1bqkbnr/pppppp1p/8/8/8/8/PPP1PPPP/RNBQKBNR r1bqkbnr/pppp1ppp/8/8/8/8/PPP1PPPP/RNBQKBNR r1bqkbnr/pp1ppppp/8/8/8/8/PPP1PPPP/RNBQKBNR rnbqkb1r/ppppppp1/8/8/8/8/PP1PPPPP/RNBQKBNR rnbqkbnr/1ppppppp/8/8/8/8/PP1PPPPP/RNBQKBNR rnbqkb1r/ppppppp1/8/8/8/8/PPPPPP2/RNBQKBNR rnbqkb1r/ppppppp1/8/8/8/8/PPPP2PP/RNBQKBNR rnbqkb1r/pppppp1p/8/8/8/8/PPPP2PP/RNBQKBNR r1bqkbnr/pp1ppppp/8/8/8/8/PPP2PPP/RNBQKBNR rnbqkb1r/p1pppppp/8/8/8/8/PPP2PPP/RNBQKBNR r1bqkbnr/pppp1ppp/8/8/8/8/PPP2PPP/RNBQKBNR r1bqkbnr/pppppp1p/8/8/8/8/PPP2PPP/RNBQKBNR r1bqkbnr/1ppppppp/8/8/8/8/2PPPPPP/RNBQKBNR rn1qkbnr/ppp1pppp/8/8/8/8/PP1PPPPP/RNBQKB1R rnb1kbnr/ppp1pppp/8/8/8/8/1PPP1PPP/RNBQKB1R rnbqk1nr/pppp1ppp/8/8/8/8/PPPPPPP1/RNBQKBN1 rnbqkbn1/ppppppp1/8/8/8/8/PPPP1PPP/RNB1KBNR rnbqkbnr/pppp1p1p/8/8/8/8/PPP1PPPP/RN1QKBNR rnb1kbnr/pppp1ppp/8/8/8/8/PPP1PPPP/RN1QKBNR rnbqkbnr/pp1ppp1p/8/8/8/8/PPP1PPPP/RN1QKBNR r1bqkbnr/pppppp1p/8/8/8/8/PPP1PPPP/RN1QKBNR _________________ _________________ _________________ _________________ | | | | | | r n b q k b . r | r n . q k b n r | r n . q k b n r | r . b q k b n r | | p p p p p p p p | p p p . p p p p | p p . . p p p p | p p p p p p p p | | . . . . . . . . | . . . . . . . . | . . . . . . . . | . . . . . . . . | | . . . . . . . . | . . . . . . . . | . . . . . . . . | . . . . . . . . | | . . . . . . . . | . . . . . . . . | . . . . . . . . | . . . . . . . . | | . . . . . . . . | . . . . . . . . | . . . . . . . . | . . . . . . . . | | P P P P . P P P | . P P P P P P P | P P P P P P P P | P P P . . P P P | | . N B Q K B N R | . N B Q K B N R | R . B Q K B N R | R . B Q K B N R | |_________________|_________________|_________________|_________________| | | | | | | r n b . k b n r | r n b . k b n r | r n b . k b n r | r n b . k b n r | | p p p p . p p p | p p p p . p p p | p p p . p p p p | p p p . p p p p | | . . . . . . . . | . . . . . . . . | . . . . . . . . | . . . . . . . . | | . . . . . . . . | . . . . . . . . | . . . . . . . . | . . . . . . . . | | . . . . . . . . | . . . . . . . . | . . . . . . . . | . . . . . . . . | | . . . . . . . . | . . . . . . . . | . . . . . . . . | . . . . . . . . | | P P P P P P . P | P P P P P P P . | P P P P . P . P | P P P P P P . P | | R . B Q K B N R | R . B Q K B N R | R . B Q K B N R | R . B Q K B N . | |_________________|_________________|_________________|_________________| | | | | | | r n b . k b n r | r n b q k . n r | r n b q k . n r | r n b q k b . r | | p p p . p p p p | p p p p . p p p | p p p p . . p p | p p p p p p p p | | . . . . . . . . | . . . . . . . . | . . . . . . . . | . . . . . . . . | | . . . . . . . . | . . . . . . . . | . . . . . . . . | . . . . . . . . | | . . . . . . . . | . . . . . . . . | . . . . . . . . | . . . . . . . . | | . . . . . . . . | . . . . . . . . | . . . . . . . . | . . . . . . . . | | P P . P P P . P | P P P P P P P P | P P P P P P P P | P P P . . P P P | | R N B Q K B N . | R N B Q K B . R | R N B Q K B . R | R N B Q K B . R | |_________________|_________________|_________________|_________________| | | | | | | r . b q k b n r | r n b . k b n r | r n b q k b n r | r n b q k b n r | | p p p p p p p p | p p p p . p p p | p p p p p p p . | p p p p p p . p | | . . . . . . . . | . . . . . . . . | . . . . . . . . | . . . . . . . . | | . . . . . . . . | . . . . . . . . | . . . . . . . . | . . . . . . . . | | . . . . . . . . | . . . . . . . . | . . . . . . . . | . . . . . . . . | | . . . . . . . . | . . . . . . . . | . . . . . . . . | . . . . . . . . | | P P P P . P P P | P . P P P P P P | P P P P . P P P | P P P P . P P P | | R N B Q K B . R | R N B Q K B . R | R N B Q K B N R | R N B Q K B N R | |_________________|_________________|_________________|_________________| | | | | | | r n b q k b n r | r . b q k b n r | r n b q k b n r | r n b q k b n r | | p . p p p p p p | p p p p p p p p | p p p p p p p . | p p p p p p . p | | . . . . . . . . | . . . . . . . . | . . . . . . . . | . . . . . . . . | | . . . . . . . . | . . . . . . . . | . . . . . . . . | . . . . . . . . | | . . . . . . . . | . . . . . . . . | . . . . . . . . | . . . . . . . . | | . . . . . . . . | . . . . . . . . | . . . . . . . . | . . . . . . . . | | P P P P . P P P | P P P . P . P P | P P P . P P P P | P P P . P P P P | | R N B Q K B N R | R N B Q K B N R | R N B Q K B N R | R N B Q K B N R | |_________________|_________________|_________________|_________________| | | | | | | r . b q k b n r | r . b q k b n r | r . b q k b n r | r n b q k b . r | | p p p p p p . p | p p p p . p p p | p p . p p p p p | p p p p p p p . | | . . . . . . . . | . . . . . . . . | . . . . . . . . | . . . . . . . . | | . . . . . . . . | . . . . . . . . | . . . . . . . . | . . . . . . . . | | . . . . . . . . | . . . . . . . . | . . . . . . . . | . . . . . . . . | | . . . . . . . . | . . . . . . . . | . . . . . . . . | . . . . . . . . | | P P P . P P P P | P P P . P P P P | P P P . P P P P | P P . P P P P P | | R N B Q K B N R | R N B Q K B N R | R N B Q K B N R | R N B Q K B N R | |_________________|_________________|_________________|_________________| | | | | | | r n b q k b n r | r n b q k b . r | r n b q k b . r | r n b q k b . r | | . p p p p p p p | p p p p p p p . | p p p p p p p . | p p p p p p . p | | . . . . . . . . | . . . . . . . . | . . . . . . . . | . . . . . . . . | | . . . . . . . . | . . . . . . . . | . . . . . . . . | . . . . . . . . | | . . . . . . . . | . . . . . . . . | . . . . . . . . | . . . . . . . . | | . . . . . . . . | . . . . . . . . | . . . . . . . . | . . . . . . . . | | P P . P P P P P | P P P P P P . . | P P P P . . P P | P P P P . . P P | | R N B Q K B N R | R N B Q K B N R | R N B Q K B N R | R N B Q K B N R | |_________________|_________________|_________________|_________________| | | | | | | r . b q k b n r | r n b q k b . r | r . b q k b n r | r . b q k b n r | | p p . p p p p p | p . p p p p p p | p p p p . p p p | p p p p p p . p | | . . . . . . . . | . . . . . . . . | . . . . . . . . | . . . . . . . . | | . . . . . . . . | . . . . . . . . | . . . . . . . . | . . . . . . . . | | . . . . . . . . | . . . . . . . . | . . . . . . . . | . . . . . . . . | | . . . . . . . . | . . . . . . . . | . . . . . . . . | . . . . . . . . | | P P P . . P P P | P P P . . P P P | P P P . . P P P | P P P . . P P P | | R N B Q K B N R | R N B Q K B N R | R N B Q K B N R | R N B Q K B N R | |_________________|_________________|_________________|_________________| | | | | | | r . b q k b n r | r n . q k b n r | r n b . k b n r | r n b q k . n r | | . p p p p p p p | p p p . p p p p | p p p . p p p p | p p p p . p p p | | . . . . . . . . | . . . . . . . . | . . . . . . . . | . . . . . . . . | | . . . . . . . . | . . . . . . . . | . . . . . . . . | . . . . . . . . | | . . . . . . . . | . . . . . . . . | . . . . . . . . | . . . . . . . . | | . . . . . . . . | . . . . . . . . | . . . . . . . . | . . . . . . . . | | . . P P P P P P | P P . P P P P P | . P P P . P P P | P P P P P P P . | | R N B Q K B N R | R N B Q K B . R | R N B Q K B . R | R N B Q K B N . | |_________________|_________________|_________________|_________________| | | | | | | r n b q k b n . | r n b q k b n r | r n b . k b n r | r n b q k b n r | | p p p p p p p . | p p p p . p . p | p p p p . p p p | p p . p p p . p | | . . . . . . . . | . . . . . . . . | . . . . . . . . | . . . . . . . . | | . . . . . . . . | . . . . . . . . | . . . . . . . . | . . . . . . . . | | . . . . . . . . | . . . . . . . . | . . . . . . . . | . . . . . . . . | | . . . . . . . . | . . . . . . . . | . . . . . . . . | . . . . . . . . | | P P P P . P P P | P P P . P P P P | P P P . P P P P | P P P . P P P P | | R N B . K B N R | R N . Q K B N R | R N . Q K B N R | R N . Q K B N R | |_________________|_________________|_________________|_________________| | | | r . b q k b n r | | p p p p p p . p | | . . . . . . . . | | . . . . . . . . | | . . . . . . . . | | . . . . . . . . | | P P P . P P P P | | R N . Q K B N R | |_________________|