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A319988 a(n) = 1 if n is divisible by the square of its largest prime factor, 0 otherwise. 10
0, 0, 0, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

1

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..65537

Index entries for characteristic functions

FORMULA

a(n) = 1 iff A071178(n) > 1.

a(n) = 1 if n > 1 and A006530(n)^2 divides n, otherwise 0.

a(n) = 1 iff n > 1 and A241917(n) = 0.

For n > 1, a(n) = A000035(A336124(n)) = A122111(n) mod 2. - Antti Karttunen, Jul 18 2020

PROG

(PARI) A319988(n) = ((n>1)&&(factor(n)[omega(n), 2]>1));

CROSSREFS

Characteristic function of A070003.

Cf. A006530, A071178, A122111, A241917, A319710, A336124.

Sequence in context: A160351 A268340 A336356 * A023969 A060039 A319710

Adjacent sequences:  A319985 A319986 A319987 * A319989 A319990 A319991

KEYWORD

nonn

AUTHOR

Antti Karttunen, Oct 04 2018

STATUS

approved

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Last modified June 23 18:45 EDT 2021. Contains 345402 sequences. (Running on oeis4.)