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 A070829 #12 Feb 26 2018 00:53:45
%S A070829 1,0,1,1,0,0,1,1,1,0,0,0,1,1,0,1,1,0,1,0,0,0,0,1,1,1,0,0,0,0,0,1,1,0,
%T A070829 0,1,0,1,1,1,0,0,0,0,0,0,1,1,1,0,0,0,0,0,0,0,1,1,0,1,0,1,0,1,1,0,0,0,
%U A070829 1,0,0,0,0,0,0,0,0,1,1,1,0
%N A070829 Array showing which primes divide n >= 2.
%C A070829 In the Kac reference this array is called rho_{p}(n) := 1 if p divides n else 0.
%C A070829 The row length sequence is A061395(n),n>=2: [1,2,1,3,2,4,1,2,3,5,2,6,4,3,...] (the index of the largest prime dividing n). All row entries beyond these numbers are 0, hence they are not shown. The n=1 row would have 0 for all entries.
%C A070829 The column sequences (without leading zeros) give for m>=1 periodic sequences with the period: 1 followed by p(m)-1 zeros. They start with n=p(m) := A000040(m).
%D A070829 Mark Kac, A Personal History of the Scottish Book, pp. 17-27, in R. D. Mauldin (ed.), The Scottish Book, Birkhäuser, Boston, Basel, 1981.
%H A070829 W. Lang, <a href="http://www.itp.kit.edu/~wl/A070829.text">First 32 rows</a>.
%F A070829 a(n, m)=1 if p(m), m>=1, divides n>=2, with the prime p(m) := A000040(m), else 0.
%e A070829 {1}, {0, 1}, {1}, {0, 0, 1}, {1, 1}, {0, 0, 0, 1}, {1}, {0, 1}, {1, 0, 1}...
%e A070829 Row n=10: {1,0,1} because p(1)=2 and p(3)= 5 divides 10.
%Y A070829 Cf. A067255 (array with multiplicities).
%K A070829 nonn,easy,tabf
%O A070829 2,1
%A A070829 _Wolfdieter Lang_, May 17 2002