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## Example ##
grayscalesImage(6) # produces image shown in screenshot to the right
</lang>
=={{header|Racket}}==
This solution uses the built-in pict library for graphics.
[[File:Grayscale-pict.png|thumb|right]]
<lang racket>
#lang racket/gui
(require slideshow/pict)
(define-values (*width* *height*) (values 400 40))
(define (shades inc)
(for/list ([scale (in-range 0 (+ 1 inc) inc)])
(round (* 255 scale))))
(define (grays increment direction)
(define colors (shades increment))
(apply hc-append
((if (eq? direction 'right) identity reverse)
(for/list ([c colors])
(colorize (filled-rectangle
(/ *width* (length colors)) *height*)
(make-color c c c))))))
(vc-append (grays 1/8 'right) (grays 1/16 'left)
(grays 1/32 'right) (grays 1/64 'left))
</lang>
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