Find the 6-digit number with no zeros where:

• No digit appears more than once.
• The sum of the last four digits equals twice the sum of the first two.
• The first two digits form a prime number when concatenated.
• Digits 2 and 3 also form a prime.
• Digits 3 and 4 also form a prime.
• Digits 4 and 5 also form a prime.
• Digit 5 itself is also a prime.
• All six digits add up to 33.

The last two digits need not form a prime.

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From Mensa Puzzle Calendar 2018 by Fraser Simpson, Workman Publishing, New York. Puzzle for October 9.

(In reply to p&p soln by Steven Lord)

The wording here is a paraphrase of the wording on the calendar. I don't recall the wording on the calendar and no longer have the page. Also the title was not the same on the calendar, and I might have thought that the word "chain" might trigger some necessity in the minds of solvers that all the pairs were so chained.

Posted by Charlie on 2018-10-24 16:21:53