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%I #13 Jul 16 2021 15:40:29
%S 91,93,95,115,117,119,117,119,121,119,121,123,121,123,125,141,143,145,
%T 143,145,147,183,185,187,185,187,189,201,203,205,203,205,207,205,207,
%U 209,213,215,217,215,217,219,217,219,221,243,245,247,245,247,249,285
%N Array read by rows: each row lists three consecutive nonprime odd numbers.
%H Robert Israel, <a href="/A129822/b129822.txt">Table of n, a(n) for n = 1..10002</a>
%p a:=proc(n) if isprime(2*n-1)=false and isprime(2*n+1)=false and isprime(2*n+3)=false then 2*n-1, 2*n+1, 2*n+3 else fi end: seq(a(n),n=1..150);
%t Flatten[Table[If[OddQ[n - 1] && PrimeQ[n - 1] == False && PrimeQ[n + 1] == False && PrimeQ[n + 3] == False, {{n - 1}, {n + 1}, {n + 3}}, {}], {n, 2, 300}]]
%t Select[Partition[Range[1,301,2],3,1],NoneTrue[#,PrimeQ]&]//Flatten (* _Harvey P. Dale_, Jul 16 2021 *)
%Y Cf. A099019 (second column), A161945 (first column).
%K nonn,tabf
%O 1,1
%A _Roger L. Bagula_, May 20 2007
%E Edited by _N. J. A. Sloane_, Jun 09 2007
%E Definition modified by _Harvey P. Dale_, Jul 16 2021
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