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 A217179 #13 Jul 01 2021 17:45:17 %S A217179 13,16,55,67,90,61,55,84,5,41,20,28,17,116,55,64,98,90,6,39,57,48,57, %T A217179 68,63,16,31,55,6,27,55,108,53,28,100,32,62,51,7,65,33,33,74,55,55,24, %U A217179 61,68,7,64,73,51,68,110,42,18,46,18,8,115,27,54,55,33,31,106 %N A217179 a(n) is the number of digits in the decimal representation of the smallest power of n that contains four consecutive identical digits. %C A217179 Number of digits in n^k is equal to floor(1 + k*log_10(n)). %H A217179 V. Raman, <a href="/A217179/b217179.txt">Table of n, a(n) for n = 2..10000</a> %t A217179 Table[k = 1; While[d = IntegerDigits[n^k]; ! MemberQ[Partition[Differences[d], 3, 1], {0, 0, 0}], k++]; Length[d], {n, 2, 100}] (* _T. D. Noe_, Oct 03 2012 *) %t A217179 ndsp[n_]:=Module[{k=1},While[SequenceCount[IntegerDigits[n^k],{x_,x_,x_,x_}] <1,k++];IntegerLength[n^k]]; Array[ndsp,70,2] (* _Harvey P. Dale_, Jul 01 2021 *) %Y A217179 Cf. A217159, A217169. %K A217179 nonn,base %O A217179 2,1 %A A217179 _V. Raman_, Sep 27 2012