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%I #3 Oct 01 2013 17:58:00
%S 2,3,3,2,3,2,5,5,5,5,3,5,5,5,3,7,7,7,7,7,7,2,7,7,7,7,7,2,3,3,7,7,7,7,
%T 3,3,5,5,5,7,7,7,5,5,5,11,11,11,11,11,11,11,11,11,11,3,11,11,11,11,11,
%U 11,11,11,11,3,13,13,13,13,13,13,13,13,13,13,13,13,7,13,13,13,13,13,13,13
%N Scan Pascal's triangle (A007318) from left to right, record largest prime factor of each entry.
%e n Pascal's Triangle
%e 1 1
%e 2 1 2 1
%e 3 1 3 3 1
%e 4 1 4 6 4 1
%e so 2,3,2 = largest prime factors of row 4 = entries position 4,5,6 in the sequence.
%e 4' 2 3 2
%o (PARI) \Largest prime factors of numbers in Pascal's triangle. pascal(n) = { local(x,y,z,f,z1); for(x=1,n, for(y=1,x-1, z=binomial(x,y); p=omega(z); f=Vec(factor(z)); z1=f[1][p]; print1(z1",") ); ) }
%K easy,nonn
%O 1,1
%A _Cino Hilliard_, Jul 25 2004
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