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 A329376 Multiplicative with a(p^e) = p when e == 2, otherwise a(p^e) = 1. 2
 1, 1, 1, 2, 1, 1, 1, 1, 3, 1, 1, 2, 1, 1, 1, 1, 1, 3, 1, 2, 1, 1, 1, 1, 5, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 6, 1, 1, 1, 1, 1, 1, 1, 2, 3, 1, 1, 1, 7, 5, 1, 2, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 3, 1, 1, 1, 1, 2, 1, 1, 1, 3, 1, 1, 5, 2, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 3, 1, 2, 1, 1, 1, 1, 1, 7, 3, 10, 1, 1, 1, 1, 1 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,4 COMMENTS Product of those distinct prime factors that occur exactly twice in the prime factorization of n, that is, whose exponent is 2. LINKS Antti Karttunen, Table of n, a(n) for n = 1..65537 FORMULA Multiplicative with a(p^e) = p when e == 2, otherwise a(p^e) = 1. a(n) <= A000196(n). PROG (PARI) A329376(n) = { my(f = factor(n)); prod(i=1, #f~, f[i, 1]^(2 == f[i, 2])); }; CROSSREFS Cf. A000196. Row 3 of array A106177, and the square roots of its row 9. Sequence in context: A211005 A162154 A134505 * A336643 A334039 A076933 Adjacent sequences:  A329373 A329374 A329375 * A329377 A329378 A329379 KEYWORD nonn,mult AUTHOR Antti Karttunen, Nov 16 2019 STATUS approved

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Last modified August 1 17:43 EDT 2021. Contains 346402 sequences. (Running on oeis4.)