A203580 a(n) = Sum{d(i)*2^i: i=0,1,...,m}, where Sum{d(i)*7^i: i=0,1,...,m}=n, d(i)∈{0,1,...,6}

0, 1, 2, 3, 4, 5, 6, 2, 3, 4, 5, 6, 7, 8, 4, 5, 6, 7, 8, 9, 10, 6, 7, 8, 9, 10, 11, 12, 8, 9, 10, 11, 12, 13, 14, 10, 11, 12, 13, 14, 15, 16, 12, 13, 14, 15, 16, 17, 18, 4, 5, 6, 7, 8, 9, 10, 6, 7, 8, 9, 10, 11, 12, 8, 9, 10, 11, 12, 13, 14, 10, 11, 12, 13, 14

Offset

0,3

Comments

Change-of-base sequence 7->2.

Links

Clark Kimberling, Table of n, a(n) for n = 0..1000

Formula

a(0)=0, a(n)=2*a(n/7) if n==0 (mod 7), a(n)=a(n-1)+1 otherwise.

Mathematica

t = Table[FromDigits[RealDigits[n, 7], 2], {n, 0, 100}] (* Clark Kimberling, Aug 03 2012 *)

Crossrefs

Cf. A033044.

Sequence in context: A125937 A173526 A245342 * A043266 A082120 A352425

Adjacent sequences: A203577 A203578 A203579 * A203581 A203582 A203583

Keyword

nonn,base

Author

Karol Bacik, Jan 03 2012

Status

approved