30 semiprimes, each less than 10⁸, form an arithmetic sequence with strictly positive common difference.

Determine all of them.

Note: A semiprime is the product of exactly two primes.

*** For an extra challenge only, find a semi-analytic solution (simple calculator + p&p) to this puzzle.

Edited on November 20, 2022, 10:54 pm

Posted by broll on 2022-11-20 22:42:28