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 pi(n) together contain each of the ten decimal digits exactly thrice.

Related solutions:

Once: pi(102756) = 9834, by G.L. Honaker, Jr. This is the only once-pandigital solution.

Twice: pi(10013236879) = 455627894, by Chuck Gaydos. This is the smallest twice-pandigital.


Contribution came from Giovanni Resta


Giovanni wrote on Jan 13, 2019:

The smallest thrice pandigital pair  should be

pi(1000112354597667) = 29847823435698.

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



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