cp's OEIS Frontend

A379486 Numbers k for which gcd(k,A003961(k))*gcd(sigma(k),A276086(k)) is 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 A379486 #13 Jan 02 2025 13:03:26
%S A379486 1,2,4,6,14,16,18,24,26,28,40,54,62,64,66,74,86,102,114,122,134,138,
%T A379486 146,152,162,169,174,176,182,184,186,206,222,234,254,270,280,282,289,
%U A379486 290,302,304,306,308,314,318,326,338,342,354,360,361,366,368,380,384,386,402,414,422,426,434,438,441,446,448,456,474,496
%N A379486 Numbers k for which gcd(k,A003961(k))*gcd(sigma(k),A276086(k)) is 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 A379486 Antti Karttunen, <a href="/A379486/b379486.txt">Table of n, a(n) for n = 1..20000</a>
%H A379486 <a href="/index/Pri#prime_indices">Index entries for sequences related to prime indices in the factorization of n</a>.
%H A379486 <a href="/index/Pri#primorialbase">Index entries for sequences related to primorial base</a>.
%H A379486 <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>.
%F A379486 {Numbers k such that A379487(k) = A379488(k)}.
%F A379486 {Numbers k such that A322361(k)/A324198(k) = A324644(k)/A342671(k)}.
%o A379486 (PARI) is_A379486 = A379485;
%Y A379486 Cf. A000203, A003961, A276086, A322361, A324198, A324644, A342671, A379485 (characteristic function), A379487, A379488.
%Y A379486 Positions of 0's in A379489.
%Y A379486 Cf. A379491 (subsequence, terms that are multiperfect numbers, A007691).
%K A379486 nonn
%O A379486 1,2
%A A379486 _Antti Karttunen_, Jan 01 2025