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PROJECT EULER · #0200

Prime-proof Squbes

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We shall define a sqube to be a number of the form, p2q3, where p and q are distinct primes.
For example, 200=5223 or 120072949=232613.

The first five squbes are 72,108,200,392, and 500.

Interestingly, 200 is also the first number for which you cannot change any single digit to make a prime; we shall call such numbers, prime-proof. The next prime-proof sqube which contains the contiguous sub-string "200" is 1992008.

Find the 200th prime-proof sqube containing the contiguous sub-string "200".

Write-up coming later

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