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 A217159 #17 Jun 26 2024 17:20:37
%S A217159 41,33,90,95,115,71,60,88,4,39,18,25,14,98,45,52,78,70,4,29,42,35,41,
%T A217159 48,44,11,21,37,4,18,36,71,34,18,64,20,39,32,4,40,20,20,45,33,33,14,
%U A217159 36,40,4,37,42,29,39,63,24,10,26,10,4,64,15,30,30,18,17,58
%N A217159 a(n) is the least value of k such that the decimal expansion of n^k contains four consecutive identical digits.
%C A217159 The term 76 appears for the first time in this sequence at n = 112044721958. - _Paul Geneau de Lamarlière_, Jun 25 2024
%H A217159 V. Raman, <a href="/A217159/b217159.txt">Table of n, a(n) for n = 2..10000</a>
%t A217159 Table[k = 1; While[! MemberQ[Partition[Differences[IntegerDigits[n^k]], 3, 1], {0, 0, 0}], k++]; k, {n, 2, 100}] (* _T. D. Noe_, Oct 01 2012 *)
%t A217159 lk[n_]:=Module[{k=1,t=Table[x_,4]},While[SequenceCount[IntegerDigits[n^k],t]< 1,k++];k];Array[lk,80,2] (* _Harvey P. Dale_, Jun 21 2022 *)
%Y A217159 Cf. A045875, A215727, A215728, A215729, A215730, A215731.
%K A217159 nonn,base
%O A217159 2,1
%A A217159 _V. Raman_, Sep 27 2012