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# app3

Basis Function Combinator

Like app1 with three items.

:   ... z y x [Q] . app3
        -----------------------------------
        ... [z ...] [Q] . infra first
          [y ...] [Q]   infra first
          [x ...] [Q]   infra first

Gentzen diagram.

## Definition

if not basis.

## Derivation

if not basis.

## Source

if basis

## Discussion

Lorem ipsum.

## Crosslinks

Lorem ipsum.