This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A176769 #14 Apr 04 2024 04:00:43
%S A176769 59049,1,729,531441,59049,6561,6561,729,81,9,31381059609,
%T A176769 205891132094649,150094635296999121,31381059609,531441,
%U A176769 150094635296999121,16677181699666569,1350851717672992089,2541865828329,8862938119652501095929
%N A176769 Smallest power of 9 whose decimal expansion contains n.
%C A176769 This is to 9 as A176763 is to 3 and as A030001 is to 2.
%H A176769 Paolo Xausa, <a href="/A176769/b176769.txt">Table of n, a(n) for n = 0..10000</a>
%F A176769 a(n) = MIN{A001019(i) such that n in decimal representation is a substring of A001019(i)}.
%F A176769 a(n) = 9^A062526(n). - _Michel Marcus_, Sep 30 2014
%e A176769 a(1) = 1 because 9^0 = 1 has "1" as a substring (not a proper substring, though).
%e A176769 a(2) = 729 because 9^3 = 729 has "2" as a substring.
%e A176769 a(3) = 531441 because 9^6 = 531441 has "3" as a substring.
%t A176769 A176769[n_] := Block[{k = -1}, While[StringFreeQ[IntegerString[9^++k], IntegerString[n]]]; 9^k]; Array[A176769, 50, 0] (* _Paolo Xausa_, Apr 04 2024 *)
%Y A176769 Cf. A001018, A030001, A176763, A176764-A176773.
%K A176769 base,easy,nonn
%O A176769 0,1
%A A176769 _Jonathan Vos Post_, Apr 25 2010
%E A176769 More terms from _Sean A. Irvine_ and _Jon E. Schoenfield_, May 05 2010
%E A176769 a(0) prepended by _Paolo Xausa_, Apr 04 2024