A048377 Append d digits d after each digit d in decimal expansion of n.

0, 11, 222, 3333, 44444, 555555, 6666666, 77777777, 888888888, 9999999999, 110, 1111, 11222, 113333, 1144444, 11555555, 116666666, 1177777777, 11888888888, 119999999999, 2220, 22211, 222222, 2223333, 22244444, 222555555, 2226666666

Offset: 0

Author

Patrick De Geest, Mar 15 1999

Keywords

• nonn
• easy
• base
• nice
• look

Comments

a(10^n) = 11 * 10^n; A007953(a(n)) = A003132(n) + A007953(n). [Reinhard Zumkeller, Jul 10 2011]

Examples

			12 becomes 1 1 2 22 = 11222.
		

Links

• Reinhard Zumkeller, Table of n, a(n) for n = 0..10000

Crossrefs

Cf. A048376.

Programs

Haskell

import Data.Char (digitToInt)
a048377 :: Integer -> Integer
a048377 n =
   read $ concat $ zipWith replicate (map ((+ 1) . digitToInt) ns) ns
      where ns = show n
-- Reinhard Zumkeller, Jul 10 2011

Mathematica

den[n_]:=Module[{idn=IntegerDigits[n]},FromDigits[Flatten[Table[ Table[ idn[[i]],{idn[[i]]+1}],{i,Length[idn]}]]]]; Array[den,30,0] (* Harvey P. Dale, Sep 04 2013 *)