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%I #12 Feb 26 2018 00:53:45
%S 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 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 1,0,0,0,0,0,0,0,0,1,1,1,0
%N Array showing which primes divide n >= 2.
%C In the Kac reference this array is called rho_{p}(n) := 1 if p divides n else 0.
%C 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 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 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 W. Lang, <a href="http://www.itp.kit.edu/~wl/A070829.text">First 32 rows</a>.
%F a(n, m)=1 if p(m), m>=1, divides n>=2, with the prime p(m) := A000040(m), else 0.
%e {1}, {0, 1}, {1}, {0, 0, 1}, {1, 1}, {0, 0, 0, 1}, {1}, {0, 1}, {1, 0, 1}...
%e Row n=10: {1,0,1} because p(1)=2 and p(3)= 5 divides 10.
%Y Cf. A067255 (array with multiplicities).
%K nonn,easy,tabf
%O 2,1
%A _Wolfdieter Lang_, May 17 2002
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