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%I #14 Sep 23 2020 03:37:18
%S 1,5,13,25,65,125,169,325,625,845,1625,2197,3125,4225,8125,10985,
%T 15625,21125,28561,40625,54925,78125,105625,142805,203125,274625,
%U 371293,390625,528125,714025,1015625,1373125,1856465,1953125,2640625
%N Numbers of the form (5^i)*(13^j).
%H Amiram Eldar, <a href="/A107466/b107466.txt">Table of n, a(n) for n = 1..10000</a>
%F Sum_{n>=1} 1/a(n) = (5*13)/((5-1)*(13-1)) = 65/48. - _Amiram Eldar_, Sep 23 2020
%F a(n) ~ exp(sqrt(2*log(5)*log(13)*n)) / sqrt(65). - _Vaclav Kotesovec_, Sep 23 2020
%t mx = 2700000; Sort@ Flatten@ Table[5^i*13^j, {i, 0, Log[5, mx]}, {j, 0, Log[13, mx/5^i]}] (* _Robert G. Wilson v_, Aug 17 2012 *)
%o (PARI) list(lim)=my(v=List(),N);for(n=0,log(lim)\log(13),N=13^n;while(N<=lim,listput(v,N);N*=5));vecsort(Vec(v)) \\ _Charles R Greathouse IV_, Jun 28 2011
%Y Cf. A003586, A003592, A003593, A003591, A003594, A003595, A003596, A003597, A003598, A003599, A107326, A107364.
%K nonn
%O 1,2
%A Douglas Winston (douglas.winston(AT)srupc.com), May 27 2005
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