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Primes from merging of 4 successive digits in decimal expansion of cos(1).
1

%I #11 Jul 01 2023 20:55:32

%S 3023,8681,6607,4297,6037,2767,5381,3947,6451,4517,5179,7951,3089,

%T 9343,4357,3571,5717,6337,1663,5417,7949,2543,3359,3517,7573,1543,

%U 4327,7549,5449,1151,2273,7823,3677,6899,7873,3067,4507,5077,8161,5851,6329,2729

%N Primes from merging of 4 successive digits in decimal expansion of cos(1).

%H Vincenzo Librandi, <a href="/A104960/b104960.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, 500][[1]], 4, 1], PrimeQ[#]&&#>1000&] (* _Vincenzo Librandi_, Apr 24 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 24 2013