[Retros] Pawn to-the-7th rank mates

[Nicolas.Dupont at math.univ-lille1.fr]

> Category C:

> bxc7#/...bxc2# etc., mate by pawn itself

>

> 1.e3 d6 2.Ba6 b5 3.Bxc8 Nd7 4.Bb7 Qb8 5.Bc6 Qb6 6.a4 O-O-O

> 7.a5 Kb8 8.axb6 Rc8 9.bxa7# (Hirokaz Onoda)


One move fewer :

1.Pc2-c4   Pd7-d5   2.Dd1-b3   Dd8-d6   3.Db3xb7   Cb8-d7
4.Db7-a6   Fc8-b7   5.Pb2-b4   O-O-O    6.Pb4-b5   Rc8-b8
7.Pb5-b6   Fb7-a8   8.Pb6xa7

Three new ones based on the same idea :

1.Pd2-d4   Pc7-c5   2.Pd4-d5   Dd8-b6   3.Dd1-d4   Db6xb2
4.Cb1-d2   Db2-a3   5.Fc1-b2   Pb7-b5   6.O-O-O    Pb5-b4
7.Rc1-b1   Pb4-b3   8.Fb2-a1   Pb3xa2

1.Pe2-e4   Pe7-e5   2.Dd1-g4   Cg8-e7   3.Dg4xg7   Ce7-c6
4.Dg7-h6   Ff8-g7   5.Pg2-g4     O-O    6.Pg4-g5   Fg7-h8
7.Pg5-g6   Dd8-g5   8.Pg6xh7

1.Pd2-d3   Pe7-e5   2.Fc1-h6   Dd8-g5   3.Pe2-e3   Dg5xg2
4.Cg1-e2   Dg2-h3   5.Ff1-g2   Pg7-g5   6.  O-O    Pg5-g4
7.Fg2xb7   Pg4-g3   8.Fb7-h1   Pg3xh2