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%I #10 Sep 03 2020 06:41:11
%S 1,2,12,40,120,208,280,396,440,520,624,672,680,760,920,1040,1160,1240,
%T 1456,1480,1640,1720,1880,2120,2288,2360,2440,2680,2840,2920,3120,
%U 3160,3320,3360,3392,3536,3560,3880,3952,3960,4040,4120,4280,4360,4368,4520
%N Numbers k such that A068976(k) divides k.
%C For n > 4 A068976(a(n)) >= 40 and almost all terms k in the sequence are such that A068976(k) = 40.
%H Amiram Eldar, <a href="/A069144/b069144.txt">Table of n, a(n) for n = 1..10000</a>
%t f[p_, e_] := If[OddQ[e], 2*(p^(e + 1) - 1)/(p^2 - 1), (p^(e + 2) + p^e - 2)/(p^2 - 1)]; s[1] = 1; s[n_] := Times @@ (f @@@ FactorInteger[n]); Select[Range[5000], Divisible[#, s[#]] &] (* _Amiram Eldar_, Sep 03 2020 *)
%o (PARI) for(n=1,10000,if(n%sumdiv(n,d,d/core(d))==0,print1(n,",")))
%Y Cf. A068976.
%K easy,nonn
%O 1,2
%A _Benoit Cloitre_, Apr 08 2002
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