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Exponent of 5 (value of j) in n-th number of form 2^i*5^j.
4

%I #15 Feb 07 2020 09:03:29

%S 0,0,0,1,0,1,0,1,2,0,1,2,0,1,2,3,0,1,2,3,0,1,2,3,0,4,1,2,3,0,4,1,2,3,

%T 0,4,1,5,2,3,0,4,1,5,2,3,0,4,1,5,2,6,3,0,4,1,5,2,6,3,0,4,1,5,2,6,3,0,

%U 7,4,1,5,2,6,3,0,7,4,1,5,2,6,3,0,7,4,1,8,5,2,6,3,0,7,4,1,8,5,2,6,3,0,7,4,1,8,5,2

%N Exponent of 5 (value of j) in n-th number of form 2^i*5^j.

%H Amiram Eldar, <a href="/A022333/b022333.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n) = A112765(A003592(n)). - _Amiram Eldar_, Feb 07 2020

%p A022333 := proc(n)

%p A112765(A003592(n)) ;

%p end proc:

%p seq(A022333(n),n=1..20) ; # _R. J. Mathar_, Aug 04 2016

%t s = {}; m = 12; Do[n = 5^k; While[n <= 5^m, AppendTo[s, n]; n *= 2], {k, 0, m}]; IntegerExponent[#, 5] & /@ Union[s]

%o (PARI) lista(nn) = {vec = vector(nn, i , i); subset = select(n->(n/(2^valuation(n,2)*5^valuation(n,5)) == 1), vec); for (i = 1, #subset, print1(valuation(subset[i], 5), ", "););} \\ _Michel Marcus_, Oct 01 2013

%Y Cf. A003592, A022332, A112765.

%K nonn

%O 1,9

%A _Clark Kimberling_