login
A295306
a(n) = +1 if tau(sigma(n)) > tau(n), -1 if n < tau(sigma(n)) < tau(n), and 0 if tau(sigma(n)) = tau(n), where tau = A000005 and sigma = A000203.
2
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, 0, 1, 1, 1, -1, 1, 1, 1, 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, 0, 1, 1, 1, 1, -1, -1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 0, 1, -1, 1, 1, 1, 1, 1
OFFSET
1
LINKS
FORMULA
a(n) = sign(A295305(n)) = sign(A000005(A000203(n)) - A000005(n)).
PROG
(PARI) A295306(n) = sign(numdiv(sigma(n)) - numdiv(n));
CROSSREFS
Cf. A037197 (positions of 0'ss), A073803 (of +1's), A073804 (of -1's).
Sequence in context: A368625 A086823 A228487 * A295303 A288226 A373253
KEYWORD
sign
AUTHOR
Antti Karttunen, Nov 21 2017
STATUS
approved