%I A006715 M2965
%S A006715 3,13,1113,3113,132113,1113122113,311311222113,13211321322113,
%T A006715 1113122113121113222113,31131122211311123113322113,
%U A006715 132113213221133112132123222113
%N A006715 Describe the previous term! (method A - initial term is 3).
%C A006715 Method A = 'frequency' followed by 'digit'-indication.
%D A006715 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences,
Academic Press, 1995 (includes this sequence).
%D A006715 J. H. Conway, The weird and wonderful chemistry of audioactive decay,
in T. M. Cover and Gopinath, eds., Open Problems in Communication
and Computation, Springer, NY 1987, pp. 173-188.
%D A006715 S. R. Finch, Mathematical Constants, Cambridge, 2003, pp. 452-455.
%D A006715 I. Vardi, Computational Recreations in Mathematica. Addison-Wesley, Redwood
City, CA, 1991, p. 4.
%H A006715 S. R. Finch, <a href="http://algo.inria.fr/bsolve/constant/cnwy/cnwy.html">
Conway's Constant</a>
%H A006715 Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/
LookandSaySequence.html">Link to a section of The World of Mathematics.</
a>
%e A006715 E.g. the term after 3113 is obtained by saying "one 3, two 1's, one 3",
which gives 132113.
%t A006715 RunLengthEncode[ x_List ] := (Through[ {First, Length}[ #1 ] ] &) /@
Split[ x ]; LookAndSay[ n_, d_:1 ] := NestList[ Flatten[ Reverse
/@ RunLengthEncode[ # ] ] &, {d}, n - 1 ]; F[ n_ ] := LookAndSay[
n, 3 ][ [ n ] ]; Table[ FromDigits[ F[ n ] ], {n, 1, 11} ] - Zerinvary
Lajos (zerinvarylajos(AT)yahoo.com), Mar 21 2007
%Y A006715 Cf. A001155, A005150, A006751, A001140, A001141, A001143, A001145, A001151,
A001154.
%Y A006715 Sequence in context: A092540 A118628 A112513 this_sequence A138487 A022507
A108583
%Y A006715 Adjacent sequences: A006712 A006713 A006714 this_sequence A006716 A006717
A006718
%K A006715 nonn,base,easy,nice
%O A006715 1,1
%A A006715 N. J. A. Sloane (njas(AT)research.att.com).
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