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A139337
Replace each digit with its number of occurrences in decimal representation of n.
8
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 11, 22, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 22, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 22, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 22, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 22, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 22, 11, 11, 11, 11, 11, 11
OFFSET
0,11
COMMENTS
A055642(a(n)) = A055642(n) for n < (10^10-1)/9; fixed points: a(A108571(n)) = A108571(n).
LINKS
EXAMPLE
a(373) = 212, since, reading the digits of 373 from left to right, 3 appeared twice, 7 once, 3 twice.
MATHEMATICA
a[n_] := IntegerDigits[n] /. Thread[{1, 2, 3, 4, 5, 6, 7, 8, 9, 0} -> DigitCount[n]] // FromDigits; Table[a[n], {n, 0, 100}] (* Jean-François Alcover, Nov 28 2013 *)
PROG
(Haskell)
import Data.List (group, sort); import Data.Maybe (mapMaybe)
a139337 n = read $ concatMap show $ mapMaybe (flip lookup ls) ds :: Int
where ls = zip (map head zss) (map length zss)
zss = group $ sort ds
ds = map (read . return) $ show n :: [Int]
-- Reinhard Zumkeller, Mar 14 2014
CROSSREFS
Sequence in context: A169853 A064263 A138838 * A231115 A040110 A140452
KEYWORD
nonn,base,look
AUTHOR
Reinhard Zumkeller, Apr 14 2008
STATUS
approved