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%I #13 Dec 17 2018 19:59:00
%S 1,2,4,6,7,8,11,13,14,16,18,19,20,21,22,23,24,25,27,28,29,32,35,36,37,
%T 38,39,42,43,44,46,47,51,53,54,55,56,57,58,59,60,62,63,64,66,69,71,72,
%U 73,74,75,76,77,79,81,82,83,84,86,87,88,89,92,95,98,100,103,106,107,109,110,111,114,116,118,119,120,121,122,125
%N Numbers n for which prime(n+7)-prime(n+6) is not a multiple of three.
%H Antti Karttunen, <a href="/A269389/b269389.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = A270189(6+n) - 6.
%F Other identities. For all n >= 1:
%F A269362(a(n)) = n.
%t Select[Range@ 125, ! Divisible[Prime[# + 7] - Prime[# + 6], 3] &] (* _Michael De Vlieger_, Mar 18 2016 *)
%t Drop[Flatten[Position[Partition[Prime[Range[200]],2,1],_?(Mod[#[[2]]- #[[1]],3]!=0&),1,Heads->False]],6]-6 (* _Harvey P. Dale_, Dec 17 2018 *)
%o (Scheme, with _Antti Karttunen_'s IntSeq-library)
%o (define A269389 (MATCHING-POS 1 1 (lambda (n) (< 0 (A137264 (+ 6 n))))))
%o (PARI) isok(n) = ((prime(n+7) - prime(n+6)) % 3) != 0; \\ _Michel Marcus_, Mar 18 2016
%Y Complement: A269399.
%Y Left inverse: A269362.
%Y Cf. A270189.
%Y Cf. also A270199.
%K nonn
%O 1,2
%A _Antti Karttunen_, Mar 16 2016
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