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A295304 a(n) = +1 if sigma(phi(n)) > n, -1 if sigma(phi(n)) < n, and 0 if sigma(phi(n)) = n, where phi = A000010 and sigma = A000203. 3
0, -1, 0, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 0, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, 1, 1, 0, 1, -1, 1, -1, 1, -1, 1, -1, 1, 1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, 1, 1, -1, 1, 1, 1, -1, 1, -1, 1, 1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, 1, 1, 1, 1, -1, 1, -1, 1, 1, 1, -1, 1, 1, 1, 1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, 1, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

1

LINKS

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

FORMULA

a(n) = sign(A295302(n)) = sign(sigma(phi(n))-n), where phi = A000010 and sigma = A000203.

PROG

(PARI) A295304(n) = sign(sigma(eulerphi(n)) - n);

CROSSREFS

Cf. A000010, A000203, A062402, A295302, A295303

Cf. A018784 (positions of 0's), A230201 (of -1's), A230203 (of +1's).

Sequence in context: A320007 A072165 A072608 * A171386 A189816 A342000

Adjacent sequences:  A295301 A295302 A295303 * A295305 A295306 A295307

KEYWORD

sign

AUTHOR

Antti Karttunen, Nov 21 2017

STATUS

approved

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Last modified September 20 17:42 EDT 2021. Contains 347588 sequences. (Running on oeis4.)