A336360 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.

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

Offset: 1

Author

Antti Karttunen, Jul 20 2020

Keywords

• nonn

Comments

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

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.

Crossrefs

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

Positions of nonnegative terms in A336386.

Programs

PARI

isA336360(n) = (bigomega(sigma(n))>=bigomega(n));