A014891 n is equal to the number of 2's in all numbers <= n written in base 6.

3878, 3879, 3880, 3881, 3882, 3883, 3888, 46656, 50534, 50535, 50536, 50537, 50538, 50539, 50544

Offset

1,1

Links

Table of n, a(n) for n=1..15.

Mathematica

Module[{nn=51000, d2}, d2=Accumulate[DigitCount[#, 6, 2]&/@Range[nn]]; Select[ Thread[ {Range[ nn], d2}], #[[1]]==#[[2]]&]][[;; , 1]] (* Harvey P. Dale, Sep 04 2024 *)

Crossrefs

Cf. A014778.

Sequence in context: A065696 A246735 A283026 * A253484 A253479 A186135

Adjacent sequences: A014888 A014889 A014890 * A014892 A014893 A014894

Keyword

nonn,base,fini,full

Author

Olivier Gérard

Extensions

List proved complete by Hugo van der Sanden (cf. A014886).

Status

approved