Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Robin's theorem, primes, and a new elementary reformulation of the
  Riemann Hypothesis   For n>1, let G(n)=\sigma(n)/(n log log n), where \sigma(n) is the sum of the
divisors of n. We prove that the Riemann Hypothesis is true if and only if 4 is
the only composite number N satisfying G(N) \ge \max(G(N/p),G(aN)), for all
prime factors p of N and all multiples aN of N. The proof uses Robin's and
Gronwall's theorems on G(n). An alternate proof of one step depends on two
properties of superabundant numbers proved using Alaoglu and Erd\H{o}s's
results.

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The categories of this paper are: hep-th
15
The categories of this paper are: nucl-ex
1
The categories of this paper are: cs
23
The categories of this paper are: solv-int
30
The categories of this paper are: q-alg
28
The categories of this paper are: alg-geom
19
The categories of this paper are: eess
20
The categories of this paper are: acc-phys
0
The categories of this paper are: hep-ph
35
The categories of this paper are: mtrl-th
16
The categories of this paper are: stat
36
The categories of this paper are: cmp-lg
31
The categories of this paper are: ao-sci
26
The categories of this paper are: bayes-an
4
The categories of this paper are: cond-mat
33
The categories of this paper are: plasm-ph