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%I #11 Sep 08 2022 08:46:15
%S 6803,52163,67103,116009,155609,196613,242243,277703,523403,706987,
%T 764189,973853,1053863,1307197,1610333,1823797,1843687,1995337,
%U 2186603,2487367,2638747,2875643,2972663,3032693,3137399,3179107,3203243,3209797,3393809,3454201,3548033,4302847,4523093
%N Primes p such that p+/-2, p+/-4 and p+/-6 are semiprimes.
%H Zak Seidov, <a href="/A266847/b266847.txt">Table of n, a(n) for n = 1..3000</a>
%e a(1)=6803 because 6797=7*971, 6799=13*523, 6801=3*2267, 6805=5*1361, 6807=3*2269, 6809=11*619.
%o (PARI) lista(nn) = {forprime(p=7, nn, if (bigomega(p-6)==2 && bigomega(p+6)==2 && bigomega(p-4)==2 && bigomega(p+4)==2 && bigomega(p-2)==2 && bigomega(p+2)==2, print1(p, ", ")););} \\ _Michel Marcus_, Jan 07 2016
%o (Magma) IsSemiprime:=func< p | &+[ k[2]: k in Factorization(p)] eq 2 >; [p: p in PrimesInInterval(3,4*10^6)| IsSemiprime(p+2) and IsSemiprime(p-2) and IsSemiprime(p+4) and IsSemiprime(p-4)and IsSemiprime(p+6) and IsSemiprime(p-6)]; // _Vincenzo Librandi_, Jan 07 2016
%Y Subsequence of A266845 and A063643.
%K nonn
%O 1,1
%A _Zak Seidov_, Jan 04 2016
%E More terms from _Michel Marcus_, Jan 07 2016