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A323152 a(n) = 1 if sigma(n) is divisible by all proper divisors of n, 0 otherwise. 2
1, 1, 1, 0, 1, 1, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 1, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

1

COMMENTS

Characteristic function of A166070.

Differs from A323153 at positions n = 1, 120, 672, 30240, 32760, ...

LINKS

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

Index entries for characteristic functions

PROG

(PARI) A323152(n) = { my(s=sigma(n)); fordiv(n, d, if((d<n)&&(s%d), return(0))); (1); };

CROSSREFS

Cf. A166070, A323153.

Sequence in context: A248392 A188318 A189206 * A192280 A266974 A075437

Adjacent sequences:  A323149 A323150 A323151 * A323153 A323154 A323155

KEYWORD

nonn

AUTHOR

Antti Karttunen, Jan 09 2019

STATUS

approved

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Last modified July 4 15:25 EDT 2020. Contains 335448 sequences. (Running on oeis4.)