This site is supported by donations to The OEIS Foundation.

 Annual appeal: Please make a donation to keep the OEIS running! Over 6000 articles have referenced us, often saying "we discovered this result with the help of the OEIS". Other ways to donate

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A107846 Number of duplicate digits of n. 3
 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 COMMENTS a(A010784(n)) = 0; a(A109303(n)) > 0. - Reinhard Zumkeller, Jul 09 2013 LINKS Reinhard Zumkeller, Table of n, a(n) for n = 0..10000 FORMULA a(n) = A055642(n) - A043537(n). EXAMPLE a(11) = 1 because 11 has two total decimal digits but only one distinct digit (1) and 2-1=1. Similarly, a(3653135) = 7 (total digits) - 4 (distinct digits: 1,3,5,6) = 3 (There are three duplicate digits here, namely, 3, 3 and 5). MAPLE A107846:=proc(q) local a, b, c, n; for n from 0 to q do a:=n; b:=[];   while a>0 do c:=a mod 10; b:=[op(b), c]; a:=trunc(a/10); od;   a:=nops(b); b:=nops({op(b)}); print(a-b); od; end: A107846(10^4); # Paolo P. Lava, Apr 18 2013 MATHEMATICA Table[Total[Select[DigitCount[n]-1, #>0&]], {n, 0, 120}] (* Harvey P. Dale, Jul 31 2013 *) PROG (Haskell) import Data.List (sort, group) a107846 = length . concatMap tail . group . sort . show :: Integer -> Int -- Reinhard Zumkeller, Jul 09 2013 CROSSREFS Cf. A055642 (Total decimal digits of n), A043537 (Distinct decimal digits of n). Sequence in context: A088918 A011726 A070109 * A179801 A065202 A045701 Adjacent sequences:  A107843 A107844 A107845 * A107847 A107848 A107849 KEYWORD base,easy,nonn AUTHOR Rick L. Shepherd, May 24, 2005 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 | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.