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%I #3 Oct 01 2013 17:58:00
%S 2,3,3,2,2,2,5,2,2,5,2,3,2,3,2,7,3,5,5,3,7,2,2,2,2,2,2,2,3,2,2,2,2,2,
%T 2,3,2,3,2,2,2,2,2,3,2,11,5,3,2,2,2,2,3,5,11,2,2,2,3,2,2,2,3,2,2,2,13,
%U 2,2,5,3,2,2,3,5,2,2,13,2,7,2,7,2,3,2,3,2,7,2,7,2,3,3,5,3,3,5,3,3,5,3,3,5,3
%N Scan Pascal's triangle (A007318) from left to right, record smallest 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, 2, 2 = smallest prime factors of row 4 = entries position 4, 5, 6 in the sequence.
%o (PARI) \Smallest 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); f=Vec(factor(z)); z1=f[1][1]; print1(z1",") ); ) }
%Y Cf. A007318.
%K easy,nonn
%O 1,1
%A _Cino Hilliard_, Jul 25 2004
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