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Primes from merging of 7 successive digits in decimal expansion of the Golden Ratio, (1+sqrt(5))/2.
31

%I #28 Feb 21 2023 17:18:39

%S 1618033,8874989,1798057,7204189,1893911,1374847,5386891,2126633,

%T 6222353,6354433,8322661,1696207,9631361,1361443,1344947,9874339,

%U 7499887,6249407,1210427,6217711,7111777,8053153,9914669,8782289

%N Primes from merging of 7 successive digits in decimal expansion of the Golden Ratio, (1+sqrt(5))/2.

%C Leading zeros are not permitted, so each term is 7 digits in length. - _Harvey P. Dale_, Oct 23 2011

%H Vincenzo Librandi, <a href="/A103793/b103793.txt">Table of n, a(n) for n = 1..1000</a>

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

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/GoldenRatio.html">Golden Ratio</a>.

%t With[{len=7},FromDigits/@Select[Partition[RealDigits[GoldenRatio, 10,1000][[1]],len,1],PrimeQ[FromDigits[#]] && IntegerLength[ FromDigits[#]] == len&]] (* _Harvey P. Dale_, Oct 23 2011 *)

%Y Cf. A001622.

%K nonn,base

%O 1,1

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

%E Broken URL to Project Gutenberg replaced by _Georg Fischer_, Jan 03 2009

%E Offset changed from 0 to 1 by _Vincenzo Librandi_, Apr 19 2013