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 A088387 Prime corresponding to largest prime power factor of n, a(1)=1. 3
 1, 2, 3, 2, 5, 3, 7, 2, 3, 5, 11, 2, 13, 7, 5, 2, 17, 3, 19, 5, 7, 11, 23, 2, 5, 13, 3, 7, 29, 5, 31, 2, 11, 17, 7, 3, 37, 19, 13, 2, 41, 7, 43, 11, 3, 23, 47, 2, 7, 5, 17, 13, 53, 3, 11, 2, 19, 29, 59, 5, 61, 31, 3, 2, 13, 11, 67, 17, 23, 7, 71, 3, 73, 37, 5, 19, 11, 13, 79, 2, 3, 41, 83, 7, 17 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Most significant prime factor of n: If n = (p_1^e_1)(p_2^e_2)(p_3^e_3)... and max(p_1^e_1,p_2^e_2,...) = p_k^e_k then a(n) = p_k. a(n*a(n)) = a(n) - Sam Alexander (amnalexander(AT)yahoo.com), Dec 15 2003 A034699(n) = a(n)^A088388(n). LINKS EXAMPLE a(6) = a(2*3) = 3 because 3^1 > 2^1 a(36) = a((2^2)(3^2)) = 3 because 3^2 > 2^2 a(12) = a((2^2)*3) = 2 because 2^2 > 3^1 MATHEMATICA f[n_] := Sort[ {#[[1]]^#[[2]], #[[1]]} & /@ FactorInteger@ n][[ -1, 2]]; Array[f, 85] (* Robert G. Wilson v, Nov 05 2007 *) CROSSREFS Sequence in context: A076690 A086287 A090662 * A197861 A180506 A162325 Adjacent sequences:  A088384 A088385 A088386 * A088388 A088389 A088390 KEYWORD easy,nonn AUTHOR Reinhard Zumkeller, Sep 28 2003 EXTENSIONS More terms from Ray Chandler, Dec 20 2003 Edited by N. J. A. Sloane at the suggestion of Stefan Steinerberger, Nov 04 2007 STATUS approved

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