A336360 - OEIS

%I #9 Jul 24 2020 10:57:28

%S 1,2,3,5,6,7,10,11,12,13,14,15,17,19,20,21,22,23,24,26,27,28,29,30,31,

%T 33,34,35,37,38,39,40,41,42,43,44,45,46,47,49,51,52,53,54,55,56,57,58,

%U 59,60,61,62,63,65,66,67,68,69,70,71,73,74,75,76,77,78,79,82,83,84,85,86,87,88,89,90,91,92,93,94,95,97

%N Numbers k for which bigomega(sigma(k)) >= bigomega(k), where bigomega (A001222) gives the number of prime factors with multiplicity, and sigma (A000203) gives the sum of divisors.

%C Numbers k such that A058063(k) >= A001222(k).

%C If terms x and y are present and gcd(x,y) = 1, then x*y is present also. This follows because both A001222 and A058063 are additive sequences, their difference A336386 is also.

%o (PARI) isA336360(n) = (bigomega(sigma(n))>=bigomega(n));

%Y Cf. A000203, A001222, A058063, A336359 (complement).

%Y Positions of nonnegative terms in A336386.

%K nonn

%O 1,2

%A _Antti Karttunen_, Jul 20 2020