login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A206714 Number of solutions (n,k) of s(k)=s(n) (mod n), where 1<=k<n and s(k)=2^(k-1). 2
0, 1, 1, 1, 2, 2, 4, 1, 2, 1, 4, 1, 4, 3, 11, 2, 2, 1, 4, 3, 2, 2, 10, 1, 2, 1, 8, 1, 7, 6, 26, 3, 4, 2, 5, 1, 2, 3, 9, 2, 6, 3, 4, 3, 4, 2, 21, 2, 2, 6, 4, 1, 2, 2, 17, 3, 2, 1, 14, 1, 12, 10, 57, 5, 6, 1, 8, 3, 5, 2, 11, 8, 2, 3, 4, 2, 6, 2, 18, 1, 4, 1, 13, 10, 6, 3, 8, 8, 7, 7, 8, 9, 4 (list; graph; refs; listen; history; text; internal format)
OFFSET
2,5
LINKS
EXAMPLE
2^6=64; the numbers 64-s(j) are 63,62,60,56,48,32, of which two are multiples of 6, so that a(6)=2.
MATHEMATICA
s[k_] := 2^(k - 1);
f[n_, k_] := If[Mod[s[n] - s[k], n] == 0, 1, 0];
t[n_] := Flatten[Table[f[n, k], {k, 1, n - 1}]]
a[n_] := Count[Flatten[t[n]], 1]
Table[a[n], {n, 2, 120}] (* A206714 *)
CROSSREFS
Sequence in context: A181633 A245204 A099320 * A230442 A034951 A317826
KEYWORD
nonn
AUTHOR
Clark Kimberling, Feb 11 2012
STATUS
approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified March 28 05:39 EDT 2024. Contains 371235 sequences. (Running on oeis4.)