A022516 Describe previous term from the right (method B - initial term is 5).

5, 51, 1151, 115112, 21125112, 211251211221, 112212211151211221, 1122122111511322112212, 21112212223112511322112212, 21112212223112512112312311221321

Offset

0,1

Comments

Method B = 'digit'-indication followed by 'frequency'.

Links

Reinhard Zumkeller, Table of n, a(n) for n = 0..21

Example

The term after 1151 is obtained by saying "1 once, 5 once, 1 twice", which gives 115112.

Prog

(Haskell)
import Data.List (group, transpose)
a022516 n = a022516_list !! n
a022516_list = 5 : f [5] :: [Integer] where
   f xs = (read $ concatMap show ys) : f ys where
          ys = concat $ transpose [map head zss, map length zss]
          zss = reverse $ group xs
-- Reinhard Zumkeller, Jan 26 2014

Crossrefs

Cf. A022481, A022488, A022514-A022520.

Sequence in context: A368838 A348023 A172403 * A003515 A022501 A134097

Adjacent sequences: A022513 A022514 A022515 * A022517 A022518 A022519

Keyword

nonn,base,easy,nice

Author

N. J. A. Sloane

Extensions

More terms from Patrick De Geest, Jun 15 1999

Status

approved