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A369048
a(n) = 1 if the arithmetic derivative of n is greater than n, otherwise 0.
2
0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 1, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0
OFFSET
0
FORMULA
a(n) = [A168036(n) > 0], where [ ] is the Iverson bracket.
a(n) = [A369049(n) == n].
MAPLE
a:= n-> `if`(add(i[2]/i[1], i=ifactors(n)[2])>1, 1, 0):
seq(a(n), n=0..121); # Alois P. Heinz, Jan 18 2024
PROG
(PARI)
A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
A369048(n) = (A003415(n) > n);
CROSSREFS
Characteristic function of A083348.
Cf. also A341625.
Sequence in context: A353480 A045698 A106197 * A011722 A373266 A276404
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jan 18 2024
STATUS
approved