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%I #24 May 08 2022 16:58:39
%S 3,11,13,19,23,37,47,53,73,97,107,131,139,163,181,193,229,239,281,307,
%T 311,349,373,379,383,409,439,443,487,491,521,577,599,601,617,619,643,
%U 683,701,709,727,739,743,761,811,821,827,829,853,863,881,883,919,937
%N Primes p such that p+1 and p-1 have the same number of distinct prime factors.
%H Charles R Greathouse IV, <a href="/A067386/b067386.txt">Table of n, a(n) for n = 1..10000</a>
%p q:= p-> isprime(p) and nops(ifactors(p+1)[2])=nops(ifactors(p-1)[2]):
%p select(q, [$1..1000])[]; # _Alois P. Heinz_, May 08 2022
%t Select[Prime[Range[200]],PrimeNu[#-1]==PrimeNu[#+1]&] (* _Harvey P. Dale_, Jun 28 2020 *)
%o (PARI) is(n)=omega(n-1)==omega(n+1) && isprime(n) \\ _Charles R Greathouse IV_, Sep 14 2015
%Y Cf. A115103 (same number of prime factors with multiplicity).
%K easy,nonn
%O 1,1
%A _Benoit Cloitre_, Feb 23 2002
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