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A336356
Characteristic function of A336359, numbers k for which A001222(A000203(k)) < A001222(k).
6
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, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0
OFFSET
1
COMMENTS
If a(x) = a(y) = 1 and gcd(x,y) = 1, then a(x*y) = 1 also. If a(x) = a(y) = 0 and gcd(x,y) = 1, then a(x*y) = 0 also. This follows because both A001222 and A058063 are additive sequences, their difference A336386 is also.
FORMULA
a(n) = 1 if A058063(n) < A001222(n), otherwise 0.
a(A336359(n)) = 1; a(A336360(n)) = 0, for all n >= 1.
PROG
(PARI) A336356(n) = (bigomega(sigma(n))<bigomega(n));
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jul 20 2020
STATUS
approved