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%I #23 Sep 08 2022 08:46:15
%S 3089,8127,8129,9981,9983,55557,92601,99441,99443,112707,132075,
%T 132077,182747,190935,190937,209477,237447,237449,239087,249687,
%U 296777,300447,313409,401427,401429,441675,441677,452637,452639,547155,604485,604487,631199,650999
%N Numbers n such that n+2, n+4, n+6, n+8, n+10, n+12 and n+14 are all semiprimes.
%C All terms are congruent to 9 or 11 (mod 18).
%H Chai Wah Wu, <a href="/A268578/b268578.txt">Table of n, a(n) for n = 1..6115</a>
%e 8127 is in sequence because 8127+2 = 11*739, 8127+4 = 47*173, 8127+6 = 3*2711, 8127+8 = 5*1627, 8127+10 = 79*103, 8127+12 = 3*2713, 8127+14 = 7*1163 are all semiprime.
%t Select[Range[400000], Union[PrimeOmega[# + {2, 4, 6, 8, 10, 12, 14}]] == {2} &]
%o (Magma) IsSemiprime := func<n | &+[m[2]: m in Factorization(n)] eq 2>; [n: n in [2..700000] | forall{i: i in [2..14 by 2] | IsSemiprime(n+i)}];
%Y Cf. A268862 (primes of the sequence).
%K nonn
%O 1,1
%A _Vincenzo Librandi_, Feb 17 2016
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