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%I #13 Aug 06 2014 09:33:54
%S 296,536,632,872,1208,1304,1544,2072,2216,2648,2984,3584,3656,3752,
%T 3848,3896,3904,3992,4328,4424,4568,4904,5624,5672,5912,6008,6104,
%U 6584,6968,7016,7256,7352,7928,8216,8264,8456,8696,8896,8936,9032,9128,9176,9368
%N Even numbers n such that n^2 is an arithmetic number.
%C Odd numbers with this property are much more numerous, cf. A107925, A003601 (arithmetic number).
%H R. J. Mathar, Michael De Vlieger, <a href="/A107924/b107924.txt">Table of n, a(n) for n = 1..10778</a> (first 443 terms from R. J. Mathar)
%p isA107924 := proc(n)
%p if type(n,'even') then
%p dvs := numtheory[divisors](n^2) ;
%p add(d,d=dvs)/nops(dvs) ;
%p if type(%,'integer') then
%p true;
%p else
%p false;
%p end if;
%p else
%p false;
%p end if;
%p end proc:
%p n := 1 :
%p for k from 2 to 100000 do
%p if isA107924(k) then
%p printf("%d %d\n",n,k) ;
%p n := n+1 ;
%p end if;
%p end do: # create b-file, _R. J. Mathar_, Jul 28 2014
%t Select[Range[2, 10000, 2], Mod[DivisorSigma[1, #^2], DivisorSigma[0, #^2]]==0&]
%Y Cf. A003601, A107925.
%K nonn,easy
%O 1,1
%A _Zak Seidov_, Jun 10 2005
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