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A295303
a(n) = +1 if n > phi(sigma(n)), -1 if n < phi(sigma(n)), and 0 if n = phi(sigma(n)), where phi = A000010 and sigma = A000203.
5
0, 0, 1, -1, 1, 1, 1, 0, -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, 1, 1, 1, 1, 1, 1, 1, 1, -1, 1, -1, 1, 1, 1, 1, 1
OFFSET
1
LINKS
FORMULA
a(n) = sign(A295301(n)) = sign(n - phi(sigma(n))).
PROG
(PARI) A295303(n) = sign(n - eulerphi(sigma(n)));
CROSSREFS
Cf. A001229 (positions of 0's), A066694 (of -1's).
Sequence in context: A086823 A228487 A295306 * A288226 A373253 A104121
KEYWORD
sign
AUTHOR
Antti Karttunen, Nov 21 2017
STATUS
approved