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%I #12 Apr 03 2024 15:26:32
%S 390625,1,25,3125,48828125,5,625,78125,78125,390625,6103515625,
%T 11920928955078125,125,931322574615478515625,244140625,15625,
%U 95367431640625,30517578125,2384185791015625,1953125,1220703125,116415321826934814453125
%N Smallest power of 5 whose decimal expansion contains n.
%C This is to 5 as A176763 is to 3 and as A030001 is to 2.
%H Paolo Xausa, <a href="/A176765/b176765.txt">Table of n, a(n) for n = 0..10000</a>
%F a(n) = MIN{A000351(i) such that n in decimal representation is a substring of A000351(i)}.
%F a(n) = 5^A062522(n). - _Michel Marcus_, Sep 30 2014
%e a(1) = 1 because 5^0 = 1 has "1" as a substring (not a proper substring, though).
%e a(2) = 25 because 5^2 = 25 has "2" as a substring.
%e a(3) = 3125 because 5^5 = 3125 has "3" as a substring.
%t A176765[n_] := Block[{k = -1}, While[StringFreeQ[IntegerString[5^++k], IntegerString[n]]]; 5^k]; Array[A176765, 50, 0] (* _Paolo Xausa_, Apr 03 2024 *)
%Y Cf. A000351, A030001, A176763, A176764-A176773.
%K base,easy,nonn
%O 0,1
%A _Jonathan Vos Post_, Apr 25 2010
%E Corrected comment by _Sean A. Irvine_, May 05 2010
%E More terms from _Sean A. Irvine_ and _Jon E. Schoenfield_, May 05 2010
%E a(0) prepended by _Paolo Xausa_, Apr 03 2024