A337542 - OEIS

A337542

Number of proper divisors d of n for which sigma(A003961(d)) >= 2*sigma(d), where sigma is the sum of divisors, and A003961(x) shifts the prime factorization of x one step towards larger primes.

0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 2, 0, 0, 0, 0, 0, 3, 0, 0, 1, 1, 0, 2, 0, 2, 0, 0, 0, 4, 0, 0, 0, 2, 0, 3, 0, 0, 2, 0, 0, 5, 0, 0, 0, 0, 0, 4, 0, 3, 0, 0, 0, 5, 0, 0, 2, 3, 0, 1, 0, 0, 0, 2, 0, 7, 0, 0, 1, 0, 0, 1, 0, 4, 2, 0, 0, 6, 0, 0, 0, 2, 0, 6, 0, 0, 0, 0, 0, 7, 0, 2, 1, 2, 0, 1, 0, 2, 3

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,18

COMMENTS

Number of terms of A337381 less than n that divide n.

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..65537

Index entries for sequences computed from indices in prime factorization

Index entries for sequences related to sigma(n)

FORMULA

a(n) = Sum_{d|n, d<n} A337383(d).

a(n) = A337541(n) - A337383(n).