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Palindromes in the decimal expansion of Pi.

The string 944449 was 'first' found at position 75557 in the decimal expansion of  Pi
counting from the first digit after the decimal point. The 3. is not counted. [Patrick De Geest]

PS Note that 75557 is a palprime !
Both palindromes are of the 'depression' form (ref. H. Heinz).

My previous record palindrome found at a dito position is
 8257528 at position 5479745   [Patrick De Geest - October 24, 1999]
My record palindromic prime found at a dito position is
 9136319 at position 9128219   [PDG - December 8, 2002]
Note that 9128219 and 9136319 are two consecutive palprimes !

Did You Know !
The string 9136319 was found at position 9128219 counting from
the first digit after the decimal point of Pi. The 3. is not counted.
Moreover both numbers are two consecutive palprimes !
Dropping the left 91 from the two numbers reveals two other primes
28219 and 36319, as well as the combination 91_363_282_19 !

See also Sloane's OEIS A038101.

The smallest palindrome that I didn't find in the first 100 million digits of Pi is
 4620264 at position ? 

The largest palindrome that I discovered present in the first 100 million digits of Pi is
palindromic triangular nr 31 or  30416261403 at position 36111197 

Donald S. McDonald noted a 13 odd-digit palindromic number fragment
after the 1722773th decimal place of number pi or
 7139999999317 at position 1722773 
The portion also contains a run of 14 consecutive odd digits
followed immediately by 11 even digits... perhaps very rare !
A neat fact published in newsgroup rec.puzzles dd. May 15 2000.



A000063 Prime Curios! Prime Puzzle
Wikipedia 63 Le Nombre 63 Numberland 63














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Patrick De Geest - Belgium - Short Bio - Some Pictures
E-mail address : pdg@worldofnumbers.com