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Primes from merging of 8 successive digits in decimal expansion of cos(1).
1

%I #12 Jul 01 2023 20:55:37

%S 86813971,97174009,31042061,47744717,83089343,78606337,26541731,

%T 47179711,32543359,35943517,59435177,89259637,57361543,44917751,

%U 63135707,35707823,23223677,36771401,67873067,62024507,84272021

%N Primes from merging of 8 successive digits in decimal expansion of cos(1).

%H Vincenzo Librandi, <a href="/A104964/b104964.txt">Table of n, a(n) for n = 1..1000</a>

%H The first <a href="http://www.worldwideschool.org/library/books/sci/math/MiscellaneousMathematicalConstants/chap14.html">15,000 digits of Cos(1)</a> as calculated by _Simon Plouffe_ at WorldWideSchool.org.

%t Select[FromDigits/@Partition[RealDigits[Cos[1], 10, 600][[1]], 8, 1], IntegerLength[#] == 8&&PrimeQ[#]&] (* _Vincenzo Librandi_ Apr 25 2013 *)

%K nonn,base

%O 1,1

%A Andrew G. West (WestA(AT)wlu.edu), Mar 30 2005

%E Offset changed from 0 to 1 by _Vincenzo Librandi_, Apr 25 2013