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1,20

Table of n, a(n) for n=1..102.

A085392 - A014673.

PrimeFactors[n_] := Flatten[ Table[ # [[1]], {1}] & /@ FactorInteger[n]]; f[n_] := Block[{gpd = Divisors[n][[ -2]]}, If[gpd == 1, 0, PrimeFactors[gpd][[ -1]] - PrimeFactors[gpd][[1]] ]]; Table[ If[n == 1, 0, f[n]], {n, 1, 102}]

Sequence in context: A046775 A221787 A204060 * A128980 A096693 A193139

Adjacent sequences: A085390 A085391 A085392 * A085394 A085395 A085396

nonn

Robert G. Wilson v and Reinhard Zumkeller, Jun 26 2003

approved