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ECO E01

ECO E00–E99 — Indian Defenses: 1.d4 Nf6 with the Nimzo-Indian, Queen's Indian, Catalan and King's Indian complexes.

2 named opening lines are classified under ECO code E01.

Catalan Opening: Open Defense — 1.d4 Nf6 2.c4 e6 3.g3 d5 4.Bg2
Catalan Opening: Tarrasch Defense — 1.d4 Nf6 2.c4 e6 3.g3 d5 4.Bg2 c5 5.Nf3 Nc6