Binary Lambda Calculus is an esoteric programming language created in 2004 by John Tromp.

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Binary lambda calculus (BLC) is a minimal, pure functional programming language invented by John Tromp in 2004,[1] based on a binary encoding of the untyped lambda calculus in De Bruijn index notation.

• Binary Lambda Calculus website
• Binary Lambda Calculus first developed in Centrum Wiskunde & Informatica
• Binary Lambda Calculus on Esolang