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ECO A51

ECO A00–A99 — Flank openings: 1.c4, 1.Nf3, 1.f4 and other first moves, plus early Indian and Benoni systems.

5 named opening lines are classified under ECO code A51.

Indian Defense: Budapest Gambit — 1.d4 Nf6 2.c4 e5
Indian Defense: Budapest Gambit Accepted — 1.d4 Nf6 2.c4 e5 3.dxe5
Indian Defense: Budapest Gambit Accepted, Fajarowicz Defense — 1.d4 Nf6 2.c4 e5 3.dxe5 Ne4
Indian Defense: Budapest Gambit Accepted, Fajarowicz Defense, Bonsdorf Variation — 1.d4 Nf6 2.c4 e5 3.dxe5 Ne4 4.a3
Indian Defense: Budapest Gambit Accepted, Fajarowicz Defense, Steiner Variation — 1.d4 Nf6 2.c4 e5 3.dxe5 Ne4 4.Qc2