18506880
domain: N
Appears in sequences
- Triangle read by rows, related to A108283.at n=53A108284
- Numbers n for which sigma(n)/n = k+1/3 with integer k.at n=8A160320
- a(n) = smallest m such that sigma(m)/m = n + 1/3.at n=3A216897
- Numbers k that divide 3*sigma(k).at n=28A245774
- Numbers k such that A017666(k) = denominator(sigma(k)/k) = 3.at n=17A245775
- Smallest x such that sigma(x)/x = 2*sigma(n)/n where sigma(n) is the sum of divisors of n.at n=17A246827
- Numbers whose numerator and denominator of their abundancy index are both Fibonacci numbers.at n=27A349687