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%I #20 Feb 09 2023 01:50:26
%S 1,2,3,5,7,10,13,17,21,25,30,35,41,47,54,61,68,76,84,93,102,112,122,
%T 132,143,154,166,178,191,204,217,231,245,260,275,291,307,323,340,357,
%U 375,393,412,431,450,470,490,511,532,554,576,598,621,644,668,692,717,742,767,793
%N Index of 2^n within sequence of numbers of form 2^i * 5^j.
%C Greedy inverse of A022332: a(n) = min {k : A022332(k) = n}. - _R. J. Mathar_, Aug 04 2016
%H Michael De Vlieger, <a href="/A022335/b022335.txt">Table of n, a(n) for n = 0..10000</a>
%F a(n) = Sum_{i=0..n} (1 + floor(log_5(2^i))). - _Michel Marcus_, Oct 02 2013
%t Table[1 + Sum[Ceiling[j*Log[5, 2]], {j, i}], {i, 0, 59}] (* _Michael De Vlieger_, Feb 08 2023 *)
%o (PARI) a(n) = sum(i=0, n, 1 + floor(log(2^i)/log(5))); \\ _Michel Marcus_, Oct 02 2013
%Y Cf. A003592, A022334.
%K nonn
%O 0,2
%A _Clark Kimberling_
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