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 A153092 #17 Jun 27 2025 16:28:21
%S A153092 1,1,1,1,3,2,3,2,20,4,5,2,9,2,27,7,12,3,3,2,3,6,6,1,18,8,2,17,2,14,55,
%T A153092 1,18,4,59,18,30,26,32,3,14,59,42,35,40,22,7,17,26,6,28,3,15,11,6,32,
%U A153092 30,18,14,4,85,3,1,65,13,64,7,18,40,8,68,5,5,6,107,7,88,25,6,3,1,21,8,12,9
%N A153092 Least k(n) such that k(n)*6^n*(6^n-1)+j is prime with j= -1 or 1 or both.
%C A153092 When n increases sum k(n) for i=1 to n / sum n for i=1 to n tends to 2*log(6)/9.
%H A153092 Pierre CAMI, <a href="/A153092/b153092.txt">Table of n, a(n) for n = 1..1000</a>.
%e A153092 1*6^1*(6^1-1)-1=29 prime as 31 so k(1)=1.
%t A153092 lkn[n_]:=Module[{c=6^n (6^n-1),k=1},While[NoneTrue[k*c+{1,-1},PrimeQ],k++];k]; Array[lkn,90] (* _Harvey P. Dale_, Feb 29 2024 *)
%Y A153092 Cf. A152414, A152090, A152091, A152093, A152094, A152095.
%K A153092 nonn
%O A153092 1,5
%A A153092 _Pierre CAMI_, Dec 18 2008