This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A157848 #23 Jan 12 2025 11:05:50
%S A157848 1,3,28,45,84,182,270,620,546,1240,1330,1638,1260,1365,2660,8128,6200,
%T A157848 6200,6944,8190,9310,7560,8190,18600,15120,18620,16380,25935,30240,
%U A157848 32760,63700,55860,40950,55800,117800,98208,105664,117800,121030,173600,167400,155610
%N A157848 Corresponding values of arithmetic means of divisors of numbers from A007340.
%C A157848 A007340 = numbers k such that the arithmetic mean of divisors of k is an integer and equal to one of the divisors of this numbers.
%H A157848 Amiram Eldar, <a href="/A157848/b157848.txt">Table of n, a(n) for n = 1..847</a> (calculated from the b-file at A007340)
%F A157848 a(n) = sigma(A007340(n))/tau(A007340(n)) = A000203(A007340(n))/A000005(A007340(n)).
%e A157848 a(3) = 28, because 28 is arithmetic mean of divisors of A007340(3)=140 and also is divisor of 140.
%o A157848 [SumOfDivisors(n) / NumberOfDivisors(n): n in[A007340(n)] ]
%o A157848 (PARI) lista(kmax) = {my(f, s, d); for(k = 1, kmax, f = factor(k); s = sigma(f); d = numdiv(f); if(!(s % d) && denominator(d / sigma(f, -1)) == 1, print1(s/d, ", ")));} \\ _Amiram Eldar_, Apr 15 2024
%Y A157848 Cf. A000203, A007340, A000005.
%K A157848 nonn
%O A157848 1,2
%A A157848 _Jaroslav Krizek_, Mar 07 2009, Mar 09 2009
%E A157848 Corrected and extended by _Jaroslav Krizek_, Mar 29 2015