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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.

A241650 Numbers m such that the GCD of the x's that satisfy sigma(x) = m is 5.

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%I A241650 #18 Dec 19 2024 06:16:14
%S A241650 6,22152,35724,125892,132444,146484,166764,182052,192504,202332,
%T A241650 239304,242580,248664,267852,291252,300612,375492,375804,434772,
%U A241650 460044,494364,536952,547992,550524,618852,628212,646668,707304,708984,752232,777852,824304,828984
%N A241650 Numbers m such that the GCD of the x's that satisfy sigma(x) = m is 5.
%H A241650 Amiram Eldar, <a href="/A241650/b241650.txt">Table of n, a(n) for n = 1..5000</a>
%H A241650 Max Alekseyev, <a href="https://oeis.org/wiki/User:Max_Alekseyev/gpscripts">PARI/GP Scripts for Miscellaneous Math Problems</a> (invphi.gp).
%e A241650 Only sigma(5) = 6, with gcd(5) = 5, so 6 is in the sequence.
%e A241650 Also, sigma(12735) = sigma(18455) = 22152, and gcd(12735, 18455) = 5, hence 22152 is in the sequence.
%o A241650 (PARI) is(k) = gcd(invsigma(k)) == 5; \\ _Amiram Eldar_, Dec 19 2024, using _Max Alekseyev_'s invphi.gp
%Y A241650 Cf. A000203, A240667, A241625, A241646, A241647, A241648, A241649.
%K A241650 nonn
%O A241650 1,1
%A A241650 _Michel Marcus_, Apr 26 2014