login
This site is supported by donations to The OEIS Foundation.
Logo

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A098729 Consider the sequence {b(n), n >= 1} of digits of the integers: 0 1 2 3 4 5 6 7 8 9 1 0 1 1 1 2 1 3 1 4 1 5 1 6 1 7 1 8 1 9 2 0... (A033307); a(n) = b(n) + n. 1
1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 12, 12, 14, 15, 16, 18, 18, 21, 20, 24, 22, 27, 24, 30, 26, 33, 28, 36, 30, 39, 33, 32, 35, 35, 37, 38, 39, 41, 41, 44, 43, 47, 45, 50, 47, 53, 49, 56, 51, 59, 54, 52, 56, 55, 58, 58, 60, 61, 62, 64, 64, 67, 66, 70, 68, 73, 70, 76, 72, 79, 75 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

Add its rank to each digit of the counting numbers (beginning with 0).

EXAMPLE

The sequence of digits of the integers is

0 1 2 3 4 5 6 7 8 9 1 0 1 1 1 2 1 3 1 4 1 5 1 6 1 7 1 8 1 9 2 0...

The 15th term, for instance, is a 1. Thus 1+15=16 is the 15th term of this sequence.

Next one is 2 (the digit) + 16 (the rank) = 18

MATHEMATICA

dgs = Flatten[IntegerDigits/@Range[0, 50]]; Plus@@@Partition[Riffle[dgs, Range[Length[dgs]]], 2] (* From Harvey P. Dale, Jan 15 2011 *)

CROSSREFS

Sequence in context: A063280 A094042 A160144 * A160939 A160927 A038124

Adjacent sequences:  A098726 A098727 A098728 * A098730 A098731 A098732

KEYWORD

base,nonn,easy

AUTHOR

Alexandre Wajnberg (alexandre.wajnberg(AT)ulb.ac.be), Sep 30 2004

EXTENSIONS

More terms from Joshua Zucker (joshua.zucker(AT)stanfordalumni.org), May 18 2006

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
Recent Additions | More pages | Superseeker | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .

Last modified February 14 18:47 EST 2012. Contains 205663 sequences.