Upper Bounds for Unitary Perfect Numbers and Unitary Harmonic Numbers
نویسندگان
چکیده
منابع مشابه
Unitary untouchable numbers
In 1973, Erdős proved that a positive proportion of numbers are untouchable; that is, not of the form s(n), where s(n) := σ(n)−n is the sum of the proper divisors of n. We investigate the analogous question where σ is replaced with similar divisor functions, such as the unitary sum-of-divisors function σ∗ (which sums those divisors d of n co-prime to n/d). We use the slightly modified version o...
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ژورنال
عنوان ژورنال: Rocky Mountain Journal of Mathematics
سال: 2007
ISSN: 0035-7596
DOI: 10.1216/rmjm/1194275935