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 A323239 a(n) = 1 if n is odd and squarefree, otherwise a(n) = 0. 3
 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0 COMMENTS Characteristic function of A056911. LINKS Antti Karttunen, Table of n, a(n) for n = 0..65537 FORMULA a(n) = A000035(n) * A008966(n). For n >= 1: a(n) = abs(A087003(n)) = abs(A099991(n)). a(n) = A085405(A156552(n)). MAPLE f:= n -> charfcn[{true}](n::odd and numtheory:-issqrfree(n)): map(f, [\$0..200]); # Robert Israel, Jan 14 2019 PROG (PARI) A323239(n) = ((n%2) && issquarefree(n)); CROSSREFS Absolute values of A087003 and A099991. Cf. A000035, A008966, A056911, A085405, A156552, A322810. Sequence in context: A215532 A191152 A139312 * A285685 A287773 A173923 Adjacent sequences:  A323236 A323237 A323238 * A323240 A323241 A323242 KEYWORD nonn AUTHOR Antti Karttunen, Jan 12 2019 STATUS approved

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Last modified September 26 05:00 EDT 2020. Contains 337346 sequences. (Running on oeis4.)