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A022517
Describe previous term from the right (method B - initial term is 6).
4
6, 61, 1161, 116112, 21126112, 211261211221, 112212211161211221, 1122122111611322112212, 21112212223112611322112212, 21112212223112612112312311221321
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 1161 is obtained by saying "1 once, 6 once, 1 twice", which gives 116112.
PROG
(Haskell)
import Data.List (group, transpose)
a022517 n = a022517_list !! n
a022517_list = 6 : f [6] :: [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
KEYWORD
nonn,base,easy,nice
EXTENSIONS
More terms from Patrick De Geest, Jun 15 1999
STATUS
approved