From Knitting Patterns Book 250.*
Note: At the left edge of each motif, work right-leaning k4tog
decreases as directed. At the right edge, work mirrored left-leaning decreases in lieu of p4tog
as follows: [slip a stitch as if to knit] 4 times, insert left needle into fronts of all four stitches, and knit together through back loops.
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Shown with a cast-on count of 37 stitches.