OFFSET
0,112
COMMENTS
LINKS
Reinhard Zumkeller, Table of n, a(n) for n = 0..10000
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).
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
(Python)
def a(n): return len(s:=str(n)) - len(set(s))
print([a(n) for n in range(105)]) # Michael S. Branicky, Jan 09 2023
CROSSREFS
KEYWORD
base,easy,nonn
AUTHOR
Rick L. Shepherd, May 24, 2005
STATUS
approved