**From New Scientist #1661, 22nd April 1989** [link]

I have two accounts at Midloids bank, both with unusual eight-digit account numbers, which are made up of a combination of only odd digits.

If either of the account numbers is split in half it gives two four-digit prime numbers. These two primes contain the same four digits, but in a different order, and with no digit repeated. Furthermore if these four-digit primes are split in half, they each give two two-digit prime numbers.

If, for both numbers, the prime formed from the first four digits is larger than the prime formed from the second four digits, what are the numbers of my accounts?

[enigma509]

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We can use the [[

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]] solver from theenigma.pylibrary to solve this puzzle.The following run file executes in 149ms.

Run:[ @repl.it ]Solution:The two account numbers are 37191973 and 71591759.