OFFSET
1,5
LINKS
Alois P. Heinz, Table of n, a(n) for n = 1..1000
Lorenz Halbeisen and Norbert Hungerbuehler, Number theoretic aspects of a combinatorial function, Notes on Number Theory and Discrete Mathematics 5(4) (1999), 138-150. (ps, pdf); see Definition 7 for the shadow transform.
N. J. A. Sloane, Transforms.
MAPLE
shadow:= proc(p) proc(n) local j; add (`if` (modp(p(j), n)=0, 1, 0), j=0..n-1) end end: f:= proc(k) proc(n) binomial (n+k-1, k) end end: a:= n-> shadow (f(4))(n): seq (a(n), n=1..120);
CROSSREFS
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Sep 23 2008
STATUS
approved