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%I #13 Sep 26 2020 03:58:18
%S 1,8,10,64,80,100,512,640,800,1000,4096,5120,6400,8000,10000,32768,
%T 40960,51200,64000,80000,100000,262144,327680,409600,512000,640000,
%U 800000,1000000,2097152,2621440,3276800,4096000,5120000,6400000,8000000
%N Numbers of form 8^i*10^j, with i, j >= 0.
%H Amiram Eldar, <a href="/A025634/b025634.txt">Table of n, a(n) for n = 1..10000</a>
%F Sum_{n>=1} 1/a(n) = (8*10)/((8-1)*(10-1)) = 80/63. - _Amiram Eldar_, Sep 26 2020
%F a(n) ~ exp(sqrt(2*log(8)*log(10)*n)) / sqrt(80). - _Vaclav Kotesovec_, Sep 26 2020
%t n = 10^6; Flatten[Table[8^i*10^j, {i, 0, Log[8, n]}, {j, 0, Log10[n/8^i]}]] // Sort (* _Amiram Eldar_, Sep 26 2020 *)
%o (PARI) list(lim)=my(v=List(), N); for(n=0, logint(lim\=1, 10), N=10^n; while(N<=lim, listput(v, N); N<<=3)); Set(v) \\ _Charles R Greathouse IV_, Jan 10 2018
%Y Subsequence of A025612.
%K easy,nonn
%O 1,2
%A _David W. Wilson_
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