Prime Numbers – Are Weird Numbers Rarer Than Prime Numbers?

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By taking a look at the first few weird numbers: $$(70, 836, 4030, 5830, 7192, 7912, 9272, 10430)$$ It is certain that prime numbers occurs more often within this range of numbers.

But are weird numbers more rare than prime numbers in the long run? Sure, by the definition of infinity, there are infinite prime numbers and infinite weird numbers. But if you calculated prime numbers and weird numbers for a finite amount of time, would prime numbers be more common than weird numbers?

This may not be very easy to explain, but I'd appreciate an attempt to keep it as simple as possible.

Best Answer

Wikipedia cites Benkoski, Stan; Erdős, Paul (April 1974). "On Weird and Pseudoperfect Numbers" for the fact the weird numbers have positive asymptotic density. But primes have zero asymptotic density, so in a sense, in a long run weird numbers are not only more abundant, but infinitely more abundant. More quantitatively, if we let $w(n)$ be the weird-number-counting function, we should have $w(n)\sim \alpha n$ for some parameter $0<\alpha<1$, whereas the prime number theorem tells us $\pi(n)\sim\frac{n}{\log n}$.