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## app3

Combinator

Like [app1] with three items.

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

### Definition

> 3 [appN]

### Discussion

See [app2].

### Crosslinks

[app1](#app1)
[app2](#app2)
[appN](#appN)
[unary](#unary)