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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A103665 Primes p such that the number of divisors of p-1 is greater than the number of divisors of p+1.

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%I A103665 #10 Aug 21 2022 19:28:29
%S A103665 13,31,37,43,61,67,73,97,101,109,113,127,151,157,163,181,193,211,229,
%T A103665 241,257,271,277,281,283,313,331,337,353,373,379,397,401,409,421,433,
%U A103665 457,463,487,521,523,541,547,571,577,601,613,617,631,641,661,673,677
%N A103665 Primes p such that the number of divisors of p-1 is greater than the number of divisors of p+1.
%C A103665 Mathematica coding by _Wouter Meeussen_ and _Robert G. Wilson v_.
%H A103665 Hugo Pfoertner, <a href="/A103665/b103665.txt">Table of n, a(n) for n = 1..10000</a>
%e A103665 a(1)=13 because d(12)=6 > d(14)=4.
%t A103665 Select[Prime[Range[2, 140]], Length[Divisors[ # - 1]] > Length[Divisors[ # + 1]] &]
%t A103665 Select[Prime[Range[200]],DivisorSigma[0,#-1]>DivisorSigma[0,#+1]&] (* _Harvey P. Dale_, Aug 21 2022 *)
%o A103665 (PARI)
%o A103665 forprime (k=2,700,if(numdiv(k-1)>numdiv(k+1),print1(k,", ")))
%o A103665 \\ _Hugo Pfoertner_, Nov 30 2017
%Y A103665 Cf. A008328 number of divisors of p-1, A008329 number of divisors of p+1, A103664, A103666, A103667.
%K A103665 nonn
%O A103665 1,1
%A A103665 _Hugo Pfoertner_, Feb 19 2005