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A103809 Primes from merging of 5 successive digits in decimal expansion of the Golden Ratio, (1+sqrt(5))/2. 24

%I

%S 39887,36563,98057,28621,41893,93911,39113,68917,26633,53693,36931,

%T 69317,93179,31793,56383,44381,38149,12203,92461,43207,32077,20771,

%U 87433,44221,47809,24007,51797,97883,56249,89069,90697,10427,11177

%N Primes from merging of 5 successive digits in decimal expansion of the Golden Ratio, (1+sqrt(5))/2.

%C Leading zeros are not permitted, so each term is 5 digits in length. - _Harvey P. Dale_, Oct 23 2011

%D Mohammad K. Azarian, Problem 123, Missouri Journal of Mathematical Sciences, Vol. 10, No. 3, Fall 1998, p. 176. Solution published in Vol. 12, No. 1, Winter 2000, pp. 61-62.

%H Vincenzo Librandi, <a href="/A103809/b103809.txt">Table of n, a(n) for n = 1..1000</a>

%H <a href="http://mathworld.wolfram.com/GoldenRatio.html">The Golden Ratio</a> as explained at MathWorld.com

%H <a href="http://www.gutenberg.org/ebooks/634">Expansion of the Golden Ratio</a> done to 20,000 digits as part of project Gutenberg.

%t With[{len=5},FromDigits/@Select[Partition[RealDigits[GoldenRatio, 10, 1000][[1]],len,1],PrimeQ[FromDigits[#]] && IntegerLength[ FromDigits[#]] == len&]] (* _Harvey P. Dale_, Oct 23 2011 *)

%K nonn,base

%O 1,1

%A Andrew G. West (WestA(AT)wlu.edu), Mar 29 2005

%E Offset changed from 0 to 1 by _Vincenzo Librandi_, Apr 22 2013

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Last modified June 20 17:21 EDT 2021. Contains 345189 sequences. (Running on oeis4.)