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 A102750 Numbers n such that square of largest prime dividing n does not divide n. 22
 2, 3, 5, 6, 7, 10, 11, 12, 13, 14, 15, 17, 19, 20, 21, 22, 23, 24, 26, 28, 29, 30, 31, 33, 34, 35, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 51, 52, 53, 55, 56, 57, 58, 59, 60, 61, 62, 63, 65, 66, 67, 68, 69, 70, 71, 73, 74, 76, 77, 78, 79, 80, 82, 83, 84, 85 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Numbers n such that the exponent of the largest prime dividing n is one. - Harvey P. Dale, May 02 2019 From Peter Munn, Sep 30 2020: (Start) 2 together with numbers on the left half of the Doudna sequence tree depicted in Antti Karttunen's 2014 comment in A005940. This sequence and A335738, considered as sets, are related by the self-inverse function A225546(.), which maps the members of either set 1:1 onto the other set. (End) LINKS Rémy Sigrist, Table of n, a(n) for n = 1..25000 EXAMPLE 63 is included because 63 = 3^2 *7 and 7 (the largest prime dividing 63) only divides 63 once. MATHEMATICA Select[Range[2, 100], FactorInteger[#][[-1, 2]]==1&] (* Harvey P. Dale, May 02 2019 *) PROG (PARI) isok(n) = my(f = factor(n)); n % f[#f~, 1]^2; \\ Michel Marcus, May 20 2014 CROSSREFS Cf. A070003 (complement, apart from the term 1 that is in neither sequence). Related to A335738 via A225546. Cf. A005940. Sequence in context: A028741 A119316 A336360 * A317092 A225354 A166111 Adjacent sequences:  A102747 A102748 A102749 * A102751 A102752 A102753 KEYWORD nonn AUTHOR Leroy Quet, Feb 09 2005 EXTENSIONS More terms from Erich Friedman, Aug 08 2005 STATUS approved

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Last modified January 28 03:42 EST 2021. Contains 340490 sequences. (Running on oeis4.)