cp's OEIS Frontend

A379492 Multiperfect numbers k for which gcd(k,A003961(k))*gcd(sigma(k),A276086(k)) is not equal to gcd(k,A276086(k))*gcd(sigma(k),A003961(k)), where A003961(n) is fully multiplicative with a(prime(i)) = prime(i+1), and A276086 is the primorial base exp-function.

%I A379492 #8 Jan 03 2025 09:34:51
%S A379492 120,672,523776,1476304896,14182439040,31998395520,518666803200,
%T A379492 13661860101120,30823866178560,740344994887680,796928461056000,
%U A379492 212517062615531520,69357059049509038080,87934476737668055040,154345556085770649600,170206605192656148480,1161492388333469337600,1802582780370364661760,9186050031556349952000
%N A379492 Multiperfect numbers k for which gcd(k,A003961(k))*gcd(sigma(k),A276086(k)) is not equal to gcd(k,A276086(k))*gcd(sigma(k),A003961(k)), where A003961(n) is fully multiplicative with a(prime(i)) = prime(i+1), and A276086 is the primorial base exp-function.
%H A379492 Antti Karttunen, <a href="/A379492/b379492.txt">Table of n, a(n) for n = 1..607</a>
%H A379492 <a href="/index/O#opnseqs">Index entries for sequences where odd perfect numbers must occur, if they exist at all</a>.
%H A379492 <a href="/index/Pri#prime_indices">Index entries for sequences related to prime indices in the factorization of n</a>.
%H A379492 <a href="/index/Pri#primorialbase">Index entries for sequences related to primorial base</a>.
%H A379492 <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>.
%o A379492 (PARI) isA379492(n) = (!(sigma(n)%n) && !A379485(n));
%Y A379492 Intersection of A007691 and A000027\A379486.
%Y A379492 Cf. A000203, A003961, A276086, A322361, A324198, A324644, A342671, A379485, A379487, A379488, A379491 (complement in A007691).
%Y A379492 Cf. A046061 (seems to be a subsequence), A323653.
%K A379492 nonn
%O A379492 1,1
%A A379492 _Antti Karttunen_, Jan 02 2025