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%I #6 Oct 15 2013 22:31:17
%S 2,3,2,3,2,3,5,3,5,2,5,7,5,3,3,5,2,7,3,5,3,7,3,5,17,7,3,7,5,2,5,23,3,
%T 5,11,3,11,7,7,5,7,3,7,11,5,3,5,19,11,13,5,3,2,13,11,5,11,7,47,3,5,11,
%U 13,7,3,7,7,29,7,17,5,23,5,19,3,7,5,5,13,7,13,3,23,7,7,5,17,11,29,13,3,7
%N Smallest one of largest prime divisors of all composite numbers between p and next prime.
%e n=128:p(128)=719,p(129)=727,d=8; composites between 2 primes:{720,721,722,723,724,725,726}; factor-sets:(2,3,5),(7,103),(2,19),(3,241),(2,3,181),(5,29),(2,3,11) least factors:{2,7,2,3,2,5,2}; Min&Max = {2,7}; largest factors:{5,103,241,181,29,11}; Min&Max = {5,241}; max-of-least=A052180(128)=7, max-of-largest=A052248(128)=241, a(128)=min-of-largest=A069898(128)=5.
%t ffi[x_] := Flatten[FactorInteger[x]]; lf[x_] := Length[FactorInteger[x]]; ba[x_] := Table[Part[ffi[x], 2*w-1], {w, 1, lf[x]}]; ep[x_] := Table[Part[ffi[x], 2*w], {w, 1, lf[x]}]; mif[x_] := Min[ba[x]]; maf[x_] := Max[ba[x]]; Table[Min[Table[maf[w], {w, Prime[n]+1, Prime[n+1]-1}]], {n, 1, 128}]
%Y Cf. A020639, A006530, A052180, A052248.
%K nonn
%O 2,1
%A _Labos Elemer_, Apr 10 2002
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