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.

A067831 Primes p such that sigma(p-6) < p.

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%I A067831 #21 Apr 24 2025 01:40:09
%S A067831 7,11,13,17,19,23,29,37,43,47,53,59,67,73,79,89,103,107,109,113,137,
%T A067831 157,163,173,179,197,199,229,233,239,257,263,269,277,283,313,317,337,
%U A067831 353,359,373,379,389,439,449,463,467,509,547,563,569,577,593,599,607
%N A067831 Primes p such that sigma(p-6) < p.
%C A067831 Superset of A046117. - _R. J. Mathar_, Sep 30 2008
%H A067831 Amiram Eldar, <a href="/A067831/b067831.txt">Table of n, a(n) for n = 1..10000</a>
%t A067831 Select[Prime[Range[4,200]],DivisorSigma[1,#-6]<#&] (* _Harvey P. Dale_, Aug 10 2023 *)
%o A067831 (PARI) isok(p) = p > 6 && isprime(p) && sigma(p-6) < p; \\ _Amiram Eldar_, Apr 24 2025
%Y A067831 Cf. A000203, A046117, A067832.
%K A067831 nonn
%O A067831 1,1
%A A067831 _Benoit Cloitre_, Feb 08 2002