cp's OEIS Frontend

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.

A069232 Numbers n such that there are exactly 2 primes p satisfying the inequality n < p < n + tau(n)^2 where tau(n) = A000005(n).

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%I A069232 #24 Sep 20 2020 15:21:54
%S A069232 2,25,85,118,119,133,141,194,209,213,235,247,253,323,326,327,329,355,
%T A069232 362,381,391,393,398,411,413,415,422,445,466,473,481,482,493,501,502,
%U A069232 511,514,515,517,519,533,535,537,538,542,543,545,551,553,573,579,581,583
%N A069232 Numbers n such that there are exactly 2 primes p satisfying the inequality n < p < n + tau(n)^2 where tau(n) = A000005(n).
%H A069232 Harvey P. Dale, <a href="/A069232/b069232.txt">Table of n, a(n) for n = 1..1000</a>
%t A069232 Select[Range[900],Length[Select[Range[#+1,#+DivisorSigma[0,#]^2-1],PrimeQ]] == 2&] (* _Harvey P. Dale_, Sep 20 2020 *)
%o A069232 (PARI) isok(n) = #select(x->isprime(x), vector(numdiv(n)^2-1, k, k+n)) == 2; \\ _Michel Marcus_, Jun 18 2017
%Y A069232 Cf. A000005, A049591, A069230, A069231, A069233.
%K A069232 easy,nonn
%O A069232 1,1
%A A069232 _Benoit Cloitre_, Apr 13 2002
%E A069232 Missing term 2 added by _Michel Marcus_, Jun 18 2017