If n2m−n=53, then 5(2m−n)=3n or 10m−5n=3n. Simplifying, we get 10m=8n and so nm=108=54.
Solution 2:
If n2m−n=53, then n2m−nn=53 or n2m−1=53. Simplifying, we get n2m=58, and so nm=58×21=54.
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