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%I #10 Mar 03 2014 12:03:12
%S 2,12,1211,211211,21122112,1221222112,122132112211,2122211213112211,
%T 21222113111221321112,123112131122311321321112,
%U 123112131112132113222113111221131211
%N Describe previous term from the right (method A - initial term is 2).
%C Method A = 'frequency' followed by 'digit'-indication.
%H Reinhard Zumkeller, <a href="/A022482/b022482.txt">Table of n, a(n) for n = 1..22</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/LookandSaySequence.html">Look and Say Sequence</a>
%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Look-and-say_sequence">Look-and-say sequence</a>
%F a(n+1) = A045918(A004086(a(n))). - _Reinhard Zumkeller_, Mar 02 2014
%e E.g. the term after 1211 is obtained by saying "two 1's, one 2, one 1", which gives 211211.
%t A022482[1]:=2;A022482[n_]:=A022482[n]=FromDigits[Flatten[{Length[#],First[#]}&/@Split[Reverse[IntegerDigits[A022482[n-1]]]]]];Map[A022482,Range[15]] (* _Peter J. C. Moses_, Apr 22 2013 *)
%o (Haskell)
%o a022482 n = a022482_list !! (n-1)
%o a022482_list = iterate (a045918 . a004086) 2
%o -- _Reinhard Zumkeller_, Mar 02 2014
%Y Cf. A022506, A006711, A022507-A022513.
%K nonn,base,easy,nice
%O 1,1
%A _Clark Kimberling_
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