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!)
A229298 Number of terms in A228919 less than or equal to 10^n. 2
5, 54, 515, 5109, 50933, 508932, 5087994 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

0.50801 < lim A229298(n)/10^n = lim A229299(n)/10^n < 0.50966.

Compare with A229299(n)/10^n.

LINKS

Table of n, a(n) for n=1..7.

J. M. Grau, A. M. Oller-Marcén, About the congruence sum_{k=1..n} k^{f(n)} == 0 (mod n), arXiv:1304.2678 [math.NT], 2013.

MATHEMATICA

fa=FactorInteger; Carlitz[k_, n_] := Mod[n-Sum[If[IntegerQ[k/(fa[n][[i, 1]]-1)], n/fa[n][[i, 1]], 0], {i, 1, Length[fa[n]]}], n]; supercar[k_, n_] := If[k == 1 || Mod[k, 2] == 0 || Mod[n, 4] > 0, Carlitz[k, n], Mod[Carlitz[k, n] - n/2, n]]; Table[Print[Length@Select[Range[10^n], supercar[#+1, #] == 0 &]], {n, 1, 7}]

CROSSREFS

Cf. A191677, A228919, A229299.

Sequence in context: A275353 A221544 A268882 * A087125 A110430 A110432

Adjacent sequences:  A229295 A229296 A229297 * A229299 A229300 A229301

KEYWORD

nonn,more,hard

AUTHOR

José María Grau Ribas, Sep 20 2013

STATUS

approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified January 18 00:50 EST 2022. Contains 350410 sequences. (Running on oeis4.)