cp's OEIS Frontend

A158294 Averages of squares of divisors of numbers in A020486 (i.e., numbers m with property that average of squares of divisors is an integer: sigma_0(m) divides sigma_2(m)).

%I A158294 #11 Jul 21 2017 12:38:59
%S A158294 1,5,7,13,25,61,35,85,65,145,181,91,125,265,217,205,175,421,481,305,
%T A158294 325,685,425,841,925,427,1105,341,817,725,595,1405,793,905,1741,455,
%U A158294 1861,1105,2245,1015,1325,2521,2665,1085,1267,1525,3121,3445,875,1885,2105
%N A158294 Averages of squares of divisors of numbers in A020486 (i.e., numbers m with property that average of squares of divisors is an integer: sigma_0(m) divides sigma_2(m)).
%C A158294 a(n) = A001157(A020486(n))/A000005(A020486(n)).
%H A158294 Zak Seidov, <a href="/A158294/b158294.txt">Table of n, a(n) for n = 1..10000</a>
%e A158294 a(12) = A001157(A020486(12))/A000005(A020486(12)) = A001157(20)/A000005(20) = 546/6 = 91.
%o A158294 (Haskell)
%o A158294 a158294 n = (a001157 $ a020486 n) `div` (a000005 $ a020486 n)
%o A158294 -- _Reinhard Zumkeller_, Jan 15 2013
%Y A158294 Cf. A000005, A001157, A020486.
%K A158294 nonn
%O A158294 1,2
%A A158294 _Jaroslav Krizek_, Mar 15 2009