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A162023 Exactly 10 consecutive odd integers starting with n are composite.

%I A162023 #9 Feb 12 2025 16:29:53
%S A162023 1131,1341,1673,1953,2183,2313,2483,2559,2979,3143,3231,3279,3471,
%T A162023 3741,3969,4029,4181,4307,4527,4763,4841,5127,5241,5361,5451,5537,
%U A162023 5603,5759,5961,6177,6401,6429,6501,6741,6927,7083,7131,7263,7373,7769,7797,7973
%N A162023 Exactly 10 consecutive odd integers starting with n are composite.
%H A162023 Robert Israel, <a href="/A162023/b162023.txt">Table of n, a(n) for n = 1..10000</a>
%e A162023 Exactly 10 consecutive odd integers 1131(2)1149 are composite while 1151 is prime.
%p A162023 R:= NULL: count:= 0: k:= 1: state:= 0:
%p A162023 while count < 100 do
%p A162023   k:= k+2;
%p A162023   if isprime(k) then
%p A162023     if state >= 10 then R:= R,k - 20; count:= count + 1;  fi;
%p A162023     state:= 0;
%p A162023   else state:= state + 1
%p A162023   fi;
%p A162023 od:
%p A162023 R; # _Robert Israel_, Feb 12 2025
%t A162023 Transpose[Select[Partition[Range[1,8001,2],11,1],PrimeQ/@ == {False,False,False,False,False,False,False,False,False,False,True}&]] [[1]] (* _Harvey P. Dale_, Nov 21 2011 *)
%Y A162023 Cf. A162022, A014076, A071904.
%K A162023 nonn
%O A162023 1,1
%A A162023 _Zak Seidov_, Jun 25 2009, typo corrected Aug 14 2009