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%I #9 Jul 28 2017 09:56:18
%S 4,6,26,34,86,134,254,274,334,386,446,566,974,1126,1226,1234,1286,
%T 1294,1546,2066,2374,2386,2554,2854,2906,2966,3086,3326,3694,3898,
%U 4054,4286,4594,4742,4846,4874,4954,5006,5218,5366,5686,5714,5854,6238,6274,6326
%N Interprimes (A024675) which are of the form s*prime, s=2.
%C Interprimes which are of the form s*prime are in A075277-A075296 (s = 2-21). Case s = 1 is impossible.
%H David A. Corneth, <a href="/A075277/b075277.txt">Table of n, a(n) for n = 1..10000</a>
%e 7646 is an interprime and 7646/2 = 3823 is prime.
%t s=2; Select[Table[(Prime[n+1]+Prime[n])/2, {n, 2, 1000}], PrimeQ[ #/s]&]
%o (PARI) first(n, {m=2}) = {my(res = List(), p); forprime(p=2, oo, if(precprime(m*p) + nextprime(m*p) == 2*m*p, listput(res, m*p); if(#res>=n,return(res))))} \\ _David A. Corneth_, Jul 26 2017
%Y Cf. A024675, A075277-A075296.
%K easy,nonn
%O 1,1
%A _Zak Seidov_, Sep 12 2002
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