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%I #27 Oct 29 2019 07:53:10
%S 1,5,29,169,145,845,1105,2405,3445,4901,2665,5525,9425,12325,12025,
%T 17225,24505,13325,32045,55205,47125,61625,69745,101065,99905,77285,
%U 124501,160225,186745,204425,239425,160225,273325,276025,292825,226525,446165,456025
%N RMS values of the RMS numbers: a(n) is the root mean square of the divisors of A140480(n).
%C Those numbers seem to be congruent to 0,1,-1 mod 5. - _Ctibor O. Zizka_, Sep 23 2008
%C No, the first terms congruent to 2 and 3 mod 5 are a(461) = 247511537 and a(1603) = 7177834573, respectively. - _Giovanni Resta_, Oct 29 2019
%H Giovanni Resta, <a href="/A141812/b141812.txt">Table of n, a(n) for n = 1..7430</a> (terms 1..455 from Andrew Weimholt, terms 456..1660 from Donovan Johnson)
%e a(5)=145, because A140480(5)=287, with divisors 1,7,41,287 and RMS(1,7,41,287) = 145.
%t rmsQ[n_] := IntegerQ[Sqrt[DivisorSigma[2, n]/DivisorSigma[0, n]]]; Reap[ For[k=1; n=1, k<10^7, k++, If[rmsQ[k], an = Sqrt[Mean[Divisors[k]^2]]; Print["k = ", k, " a(", n++, ") = ", an]; Sow[an]]]][[2, 1]] (* _Jean-François Alcover_, Dec 04 2015 *)
%o (PARI) for(n=1,1e6,if(issquare(sumdiv(n,d,d^2)/numdiv(n),&s) && denominator(s)==1,print1(s", "))) \\ _Charles R Greathouse IV_, Mar 08 2013
%Y Cf. A140480, A141813, A141814, A141815, A141816.
%K nonn
%O 1,2
%A _Andrew Weimholt_, Jul 07 2008
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