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PROJECT EULER · #0127

abc-hits

Statement only · SolvedOriginal problem ↗

The radical of n, rad(n), is the product of distinct prime factors of n. For example, 504=23×32×7, so rad(504)=2×3×7=42.

We shall define the triplet of positive integers (a,b,c) to be an abc-hit if:

  1. gcd(a,b)=gcd(a,c)=gcd(b,c)=1
  2. a<b
  3. a+b=c
  4. rad(abc)<c

For example, (5,27,32) is an abc-hit, because:

  1. gcd(5,27)=gcd(5,32)=gcd(27,32)=1
  2. 5<27
  3. 5+27=32
  4. rad(4320)=30<32

It turns out that abc-hits are quite rare and there are only thirty-one abc-hits for c<1000, with c=12523.

Find c for c<120000.

Write-up coming later

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