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%I #6 Jan 10 2015 13:50:13
%S 419,521,809,1049,1151,1721,1931,1949,2027,2111,2309,2591,2729,2999,
%T 3119,3359,3371,3389,3557,3581,3821,4229,4241,4271,4337,4421,4481,
%U 4547,5021,5879,6089,6131,6299,6449,6689,6761,6779,6791,6947,7307,7331,7349,7559
%N Prime number n, lesser of twin primes, both isolated from neighboring primes by more than +- 6.
%H Harvey P. Dale, <a href="/A138062/b138062.txt">Table of n, a(n) for n = 1..1000</a>
%e 419,421 = twin primes -- isolation +- 6 (or more)
%e 419-2 = 417 (3*139) 421+2 = 423 (3*3*47)
%e 419-4 = 415 (5*83) 421+4 = 425 (5*5*17)
%e 419-6 = 413 (7*59) 421+6 = 427 (7*61)
%t q=6;s="";For[i=1,i<10^2*5,n=Prime[i];m=n+2;If[PrimeQ[m],a=0;For[j=2,j<=q,If[PrimeQ[n-j]||PrimeQ[m+j],a=1;Break[]];j=j+2];If[a==0,s=s<>ToString[n]<>","]];i++ ];Print[s]
%t tp6Q[b_]:=Module[{d=Differences[b]},d[[2]]==2&&d[[1]]>6&&d[[3]]>6]; Transpose[ Select[Partition[Prime[Range[1000]],4,1],tp6Q]][[2]] (* _Harvey P. Dale_, Jan 10 2015 *)
%K nonn
%O 1,1
%A _Vladimir Joseph Stephan Orlovsky_, May 02 2008
%E Definition corrected by and more terms from _Harvey P. Dale_, Jan 10 2015
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