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 A070023 #8 Jun 12 2022 02:58:38
%S A070023 1,2,3,4,5,6,8,9,10,12,15,16,18,20,24,25,30,32,36,40,45,48,50,60,64,
%T A070023 72,75,80,90,96,100,120,125,128,144,150,160,180,192,200,225,240,250,
%U A070023 256,288,300,320,360,375,384,400,450,480,500,512,576,600,625,640,720,750
%N A070023 1/n has period 1 in base 10 (including terminating decimals).
%F A070023 a(n) = A070022(n)/11. Numbers of the form a*b*c where a is in {1, 3, 9}, b is a power of 2 and c is a power of 5.
%e A070023 12 is in the sequence since 1/12 = 0.08333333333...
%e A070023 11 is not since 1/11 = 0.0909090909...
%e A070023 10 is in, since 1/10 = 0.1000000... = 0.099999999...
%t A070023 Select[Range[750], Length[RealDigits[1/#][[1, -1]]] <= 1 &] (* _Amiram Eldar_, Jun 12 2022 *)
%Y A070023 Cf. A003592, A069105, A070021, A070022.
%K A070023 base,nonn
%O A070023 1,2
%A A070023 _Henry Bottomley_, Apr 12 2002