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%I #9 Apr 24 2024 12:30:08
%S 13,113,111113,411113,311113141,311113114231141,511113214123331141142,
%T 511112113314121123131132233241142151,
%U 711312313214115321122223124331232233241142251,411412213214115221522423224125431432233241142143151153171
%N A two-digit Look-and-Say sequence starting with 13: each term summarizes the increasing two-digit substrings of the previous term.
%C a(22) is the first term containing a zero; this is due to the fact that a(21) is the first term having exactly 10 occurrences of a two-digit number, namely 10 x 42.
%H Reinhard Zumkeller, <a href="/A221369/b221369.txt">Table of n, a(n) for n = 0..1000</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>
%H Reinhard Zumkeller, <a href="/A209234/a209234.hs.txt">Haskell program for two-digit Look-and-Say sequences</a>
%e a(0) = 11: 1 x 13 --> a(1) = 113;
%e a(1) = 113: 1 x 11 and 1 x 13 --> a(2) = 111113;
%e a(2) = 111113: 4 x 11 and 1 x 13 --> a(3) = 411113;
%e a(3) = 411113: 3 x 11, 1 x 13 and 1 x 41 --> a(4) = 311113141.
%o (Haskell) -- See Link.
%Y Cf. A005151, A047842.
%Y Cf. A209234 (start=10), A209233 (start=11), A221368 (start=12), A221372 (start=19), A221373 (start=99).
%K nonn,base
%O 0,1
%A _Reinhard Zumkeller_, Jan 13 2013