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%I #12 Sep 08 2022 08:45:11
%S 2,30,72,144,312,336,510,690,990,1122,1254,1272,1410,2082,2376,2508,
%T 2586,2664,2802,3060,3096,3180,3432,3510,3684,4062,4506,5526,5790,
%U 6174,7224,8064,8388,9078,9390,9504,10698,10794,10884,10992,11046,11334
%N Numbers k such that k*prime(k) -+ 1 are twin primes.
%C Intersection of A086172 and A086173. See also A086174, A086175, A086176, A086177.
%H Vincenzo Librandi, <a href="/A085637/b085637.txt">Table of n, a(n) for n = 1..1000</a>
%e k=30 is a term because 30*prime(30) +- 1 = 3390 +- 1 are twin primes.
%t Select[Range[15000], PrimeQ[ # Prime[ # ] - 1] && PrimeQ[ # Prime[ # ] + 1] &]
%o (Magma) [n: n in [1..11500] | IsPrime(n*NthPrime(n) - 1) and IsPrime(n*NthPrime(n) + 1) ]; // _Vincenzo Librandi_, Oct 05 2012
%Y Cf. A086172, A086173, A086174, A086175, A086176, A086177.
%K easy,nonn
%O 1,1
%A _Zak Seidov_, Jul 11 2003
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