Problems & Puzzles: Puzzles

Problem 71. n & pi(n) such that... G. L. Honaker, Jr. sent the following nice puzzle: Find the smallest number n such that n and (n) together contain each of the ten decimal digits exactly thrice. Related solutions: Once: (102756) = 9834, by G.L. Honaker, Jr. This is the only once-pandigital solution. Twice: (10013236879) = 455627894, by Chuck Gaydos. This is the smallest twice-pandigital.

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Contribution came from Giovanni Resta

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Giovanni wrote on Jan 13, 2019:

The smallest thrice pandigital pair  should be

pi(1000112354597667) = 29847823435698.

I used the program primecount by Kim Walisch ( 
https://github.com/kimwalisch/primecount ) to find a suitable starting 
point and to check this result, which is too large for Mathematica.
 

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