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.

A343113 Numbers having exactly 1 divisor of the form 8*k + 5.

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%I A343113 #11 Apr 06 2021 10:36:29
%S A343113 5,10,13,15,20,21,25,26,29,30,35,37,39,40,42,50,52,53,55,58,60,61,63,
%T A343113 69,70,74,75,77,78,80,84,87,91,93,95,100,101,104,106,109,110,111,115,
%U A343113 116,120,122,126,133,138,140,141,143,147,148,149,150,154,155
%N A343113 Numbers having exactly 1 divisor of the form 8*k + 5.
%H A343113 Jianing Song, <a href="/A343113/b343113.txt">Table of n, a(n) for n = 1..10000</a>
%e A343113 52 is a term since among the divisors of 52 (namely 1, 2, 4, 13, 26 and 52), the only divisor congruent to 5 modulo 8 is 13.
%o A343113 (PARI) res(n,a,b) = sumdiv(n, d, (d%a) == b)
%o A343113 isA343113(n) = (res(n,8,5) == 1)
%Y A343113 Numbers having m divisors of the form 8*k + i: A343107 (m=1, i=1), A343108 (m=0, i=3), A343109 (m=0, i=5), A343110 (m=0, i=7), A343111 (m=2, i=1), A343112 (m=1, i=3), this sequence (m=1, i=5), A141164 (m=1, i=7).
%Y A343113 Indices of 1 in A188171.
%Y A343113 A007521 is a subsequence.
%K A343113 nonn,easy
%O A343113 1,1
%A A343113 _Jianing Song_, Apr 05 2021