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 A021070 #24 Jun 09 2025 09:02:41
%S A021070 0,1,5,1,5,1,5,1,5,1,5,1,5,1,5,1,5,1,5,1,5,1,5,1,5,1,5,1,5,1,5,1,5,1,
%T A021070 5,1,5,1,5,1,5,1,5,1,5,1,5,1,5,1,5,1,5,1,5,1,5,1,5,1,5,1,5,1,5,1,5,1,
%U A021070 5,1,5,1,5,1,5,1,5,1,5,1,5,1,5,1,5,1,5,1,5,1,5,1,5,1,5,1,5,1,5
%N A021070 Decimal expansion of 1/66.
%H A021070 <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (0,1).
%F A021070 Multiplicative with a(2^e) = 5, a(p^e) = 1 otherwise. - _David W. Wilson_, Jun 12 2005
%F A021070 Dirichlet g.f.: zeta(s) * (1 + 1/2^(s-2)). - _Amiram Eldar_, Jun 09 2025
%e A021070 0.015151515151515151515151515...
%t A021070 Join[{0},RealDigits[1/66,10,120][[1]]] (* or *) PadRight[{0},120,{5,1}] (* _Harvey P. Dale_, Dec 26 2021 *)
%Y A021070 A010686 shifted right.
%K A021070 nonn,cons,mult,easy
%O A021070 0,3
%A A021070 _N. J. A. Sloane_