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 A007948 Largest cubefree number dividing n. 15
 1, 2, 3, 4, 5, 6, 7, 4, 9, 10, 11, 12, 13, 14, 15, 4, 17, 18, 19, 20, 21, 22, 23, 12, 25, 26, 9, 28, 29, 30, 31, 4, 33, 34, 35, 36, 37, 38, 39, 20, 41, 42, 43, 44, 45, 46, 47, 12, 49, 50, 51, 52, 53, 18, 55, 28, 57, 58, 59, 60, 61, 62, 63, 4, 65, 66, 67, 68, 69, 70, 71, 36, 73 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS a(n) = max{A212793(A027750(n,k)) * A027750(n,k): k=1..A000005(n)}. - Reinhard Zumkeller, May 27 2012 LINKS Reinhard Zumkeller, Table of n, a(n) for n = 1..10000 H. Bottomley, Some Smarandache-type multiplicative functions. F. Smarandache, Only Problems, Not Solutions!. FORMULA Multiplicative with a(p^e) = p^(min(e, 2)). - David W. Wilson, Aug 01 2001 a(n) = A071773(n)*A007947(n). - observed by Velin Yanev, Aug 20 2017, confirmed by Antti Karttunen, Nov 28 2017 a(n) = n / A062378(n) = n / A003557(A003557(n)). - Antti Karttunen, Nov 28 2017 MATHEMATICA Table[Apply[Times, FactorInteger[n] /. {p_, e_} /; p > 0 :> p^Min[e, 2]], {n, 73}] (* Michael De Vlieger, Jul 18 2017 *) PROG (Haskell) a007948 = last . filter ((== 1) . a212793) . a027750_row -- Reinhard Zumkeller, May 27 2012, Jan 06 2012 (PARI) a(n) = my(f=factor(n)); for (i=1, #f~, f[i, 2] = min(f[i, 2], 2)); factorback(f); \\ Michel Marcus, Jun 09 2014 (Scheme, with memoization-macro definec) (definec (A007948 n) (if (= 1 n) n (* (expt (A020639 n) (min 2 (A067029 n))) (A007948 (A028234 n))))) ;; Antti Karttunen, Nov 28 2017 CROSSREFS Cf. A003557, A004709, A007947, A058035, A062378, A027748, A124010, A197863. Sequence in context: A272573 A083501 A007922 * A038389 A058223 A245355 Adjacent sequences:  A007945 A007946 A007947 * A007949 A007950 A007951 KEYWORD nonn,mult AUTHOR R. Muller EXTENSIONS More terms from Henry Bottomley, Jun 18 2001 STATUS approved

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