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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A138470 Number of numbers less than n having a smaller sum of digits. 4
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 3, 6, 9, 12, 15, 18, 21, 24, 27, 29, 6, 10, 14, 18, 22, 26, 30, 34, 37, 39, 10, 15, 20, 25, 30, 35, 40, 44, 47, 49, 15, 21, 27, 33, 39, 45, 50, 54, 57, 59, 21, 28, 35, 42, 49, 55, 60, 64, 67, 69, 28, 36, 44, 52, 59, 65 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

a(n) + A138471(n) + A138472(n) = n.

LINKS

R. Zumkeller, Table of n, a(n) for n = 0..1500

Index entries for Colombian or self numbers and related sequences

EXAMPLE

a(42)=#{0,1,2,3,4,5,10,11,12,13,14,20,21,22,23,30,31,32,40,41}=20.

MAPLE

digitsum:=proc(n) options operator, arrow: add(convert(n, base, 10)[j], j=1.. nops(convert(n, base, 10))) end proc: a:=proc (n) local ct, j: ct:=0: for j from 0 to n-1 do if digitsum(j) < digitsum(n) then ct:=ct+1 else end if end do: ct end proc: seq(a(n), n=0..75); # Emeric Deutsch, Mar 31 2008

CROSSREFS

Cf. A007953.

Sequence in context: A156207 A061486 A264600 * A325454 A112875 A113018

Adjacent sequences:  A138467 A138468 A138469 * A138471 A138472 A138473

KEYWORD

nonn,base,look

AUTHOR

Reinhard Zumkeller, Mar 19 2008

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 October 17 14:20 EDT 2019. Contains 328113 sequences. (Running on oeis4.)