%I #6 Sep 17 2023 11:08:49
%S 47,79,83,89,113,127,157,163,167,211,251,257,293,317,331,353,359,367,
%T 373,379,383,389,397,401,439,443,449,467,479,487,491,499,503,541,547,
%U 557,577,587,607,647,673,677,683,691,701,709,719,727,733,739,743,751
%N Lesser of pairs of single (non-twin) primes.
%C Primes p such that p-/+2, nextprime(p)-/+2 are not primes. Cf. A007510 Single (or isolated or non-twin) primes.
%H Harvey P. Dale, <a href="/A126095/b126095.txt">Table of n, a(n) for n = 1..1000</a>
%e 47 and 53 are two consecutive primes while 47-/+2, 53-/+2 are not primes;
%e 79 and 83 are two consecutive primes while 79-/+2, 83-/+2 are not primes.
%t sntpQ[{a_,b_}]:=NoneTrue[Flatten[{a+{2,-2},b+{2,-2}}],PrimeQ]; Transpose[ Select[ Partition[ Prime[Range[200]],2,1],sntpQ]][[1]] (* The program uses the NoneTrue function from Mathematica version 10 *) (* _Harvey P. Dale_, Jul 22 2016 *)
%Y Cf. A007510.
%K nonn
%O 1,1
%A _Zak Seidov_, Mar 03 2007
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