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%I #9 Apr 04 2024 07:52:41
%S 4826809,1,2197,13,4826809,28561,169,2197,28561,169,10604499373,
%T 51185893014090757,371293,13,51185893014090757,815730721,169,62748517,
%U 137858491849,2197,1461920290375446110677,2197,23298085122481
%N Smallest power of 13 whose decimal expansion contains n.
%C This is to 13 as A176763 is to 3 and as A030001 is to 2.
%H Paolo Xausa, <a href="/A176772/b176772.txt">Table of n, a(n) for n = 0..10000</a>
%F a(n) = MIN{A001022(i) such that n in decimal representation is a substring of A001022(i)}.
%e a(1) = 1 because 13^0 = 1 has "1" as a substring (not a proper substring, though).
%e a(2) = 2197 because 13^3 = 2197 has "2" as a substring.
%e a(3) = 13 because 13^1 = 13 has "3" as a substring.
%t A176772[n_] := Block[{k = -1}, While[StringFreeQ[IntegerString[13^++k], IntegerString[n]]]; 13^k]; Array[A176772, 50, 0] (* _Paolo Xausa_, Apr 04 2024 *)
%Y Cf. A001022, A030001, A176763, A176764-A176773.
%K base,easy,nonn
%O 0,1
%A _Jonathan Vos Post_, Apr 25 2010
%E More terms from _Sean A. Irvine_ and _Jon E. Schoenfield_, May 05 2010
%E a(0) prepended by _Paolo Xausa_, Apr 04 2024