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A367841 Numbers k such that k, k + 2, k + 4, k + 6, k + 8, k + 10, and k + 12 are all triprimes (A014612).

%I A367841 #17 Jan 01 2024 00:57:50
%S A367841 151401,151403,151405,151407,179535,201085,247349,248411,250933,
%T A367841 250935,292407,298433,322215,379761,441327,482691,482693,499907,
%U A367841 508671,517427,584219,584221,586257,586259,605207,705055,705057,705059,718193,726563,727639,728815,812601,814247,814249,814251,831385
%N A367841 Numbers k such that k, k + 2, k + 4, k + 6, k + 8, k + 10, and k + 12 are all triprimes (A014612).
%C A367841 All terms are odd, because if k is even, at least one of k, k + 2, k + 4 and k + 6 is divisible by 8.
%C A367841 In the case of a(1) = 151401, k + 14, k + 16 and k + 18 are also triprimes.
%C A367841 In the case of a(143) = 2560187, k + 14, k + 16, k + 18 and k + 20 are also triprimes.
%H A367841 Robert Israel, <a href="/A367841/b367841.txt">Table of n, a(n) for n = 1..10000</a>
%e A367841 a(5) = 179535 is a term because
%e A367841 179535 = 3 * 5 * 11969
%e A367841 179535 + 2 = 179537 = 17 * 59 * 179
%e A367841 179535 + 4 = 179539 = 29 * 41 * 151
%e A367841 179535 + 6 = 179541 = 3 * 3 * 19949
%e A367841 179535 + 8 = 179543 = 7 * 13 * 1973
%e A367841 179535 + 10 = 179545 = 5 * 149 * 241
%e A367841 179535 + 12 = 179547 = 3 * 97 * 617
%e A367841 are all triprimes.
%p A367841 filter:= (t -> andmap(x -> numtheory:-bigomega(x)=3, [t,t+2,t+4,t+6,t+8,
%p A367841 t+10,t+12])):
%p A367841 select(filter, [seq(i,i=1 .. 10^6, 2)]);
%Y A367841 Cf. A014612.
%K A367841 nonn
%O A367841 1,1
%A A367841 _Zak Seidov_ and _Robert Israel_, Dec 31 2023