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.

A171263 Primes of the form 1 + 4-multiperfect numbers.

This page as a plain text file.
%I A171263 #10 Mar 19 2018 06:43:35
%S A171263 30241,2178541,23569921,66433720321,630532357710420079508428362350593,
%T A171263 1928622300236318049928258133164033,
%U A171263 651350717502447739281012140234441171379683329
%N A171263 Primes of the form 1 + 4-multiperfect numbers.
%C A171263 A subsequence of A093034. If p is a term of this sequence then for each positive integer k, x=p^k is a solution for the equation sigma(phi(x))=4(x-1). See comment lines of the sequence A093034.
%e A171263 p=30241 is prime and sigma(p-1)/(p-1)=4, so p is in the sequence.
%Y A171263 Cf. A027687, A093034, A171264, A171265.
%K A171263 fini,full,nonn
%O A171263 1,1
%A A171263 _M. F. Hasler_ and _Farideh Firoozbakht_, Apr 15 2010