login
A072463
Shadow transform of sigma(n), A000203, starting with 0, sigma(1), sigma(2), ...
1
0, 1, 1, 2, 2, 1, 2, 2, 2, 1, 1, 1, 3, 2, 3, 2, 1, 1, 3, 1, 2, 2, 1, 1, 4, 1, 1, 1, 2, 1, 3, 3, 3, 1, 1, 1, 3, 1, 2, 2, 2, 1, 4, 1, 2, 2, 1, 1, 5, 1, 1, 1, 1, 1, 3, 1, 3, 2, 1, 1, 6, 1, 3, 2, 1, 1, 1, 1, 2, 1, 1, 1, 8, 1, 2, 1, 1, 1, 2, 1, 3, 1, 1, 1, 6, 1, 1, 1, 1, 1, 5, 2, 1, 3, 1, 1, 5, 1, 3, 1, 1, 1, 2, 1, 3
OFFSET
0,4
LINKS
Nicholas John Bizzell-Browning, LIE scales: Composing with scales of linear intervallic expansion, Ph. D. Thesis, Brunel Univ. (UK, 2024). See p. 39.
Lorenz Halbeisen and Norbert Hungerbuehler, Number theoretic aspects of a combinatorial function, Notes on Number Theory and Discrete Mathematics 5(4) (1999), 138-150; see Definition 7 for the shadow transform.
N. J. A. Sloane, Transforms.
MAPLE
s:= n-> `if`(n=0, 0, numtheory[sigma](n)):
a:= n-> add(`if`(modp(s(j), n)=0, 1, 0), j=0..n-1):
seq(a(n), n=0..120); # Alois P. Heinz, Sep 16 2019
CROSSREFS
Cf. A000203.
Sequence in context: A270747 A214517 A230594 * A128853 A136165 A134193
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Aug 02 2002
STATUS
approved