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A209234 A two-digit Look-and-Say sequence starting with 10: each term summarizes the increasing two-digit substrings of the previous term.

%I A209234 #18 Feb 16 2025 08:33:16
%S A209234 10,110,110111,101110311,101103210311131,101203310311113121231132,
%T A209234 101203210411312213120121123431132133,
%U A209234 201103104210311512413220421122123331232133134141143,101203204310411412313214115220421222223124431232333134341242143151
%N A209234 A two-digit Look-and-Say sequence starting with 10: each term summarizes the increasing two-digit substrings of the previous term.
%H A209234 Reinhard Zumkeller, <a href="/A209234/b209234.txt">Table of n, a(n) for n = 0..1000</a>
%H A209234 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/LookandSaySequence.html">Look and Say Sequence</a>
%H A209234 Wikipedia, <a href="http://en.wikipedia.org/wiki/Look-and-say_sequence">Look-and-say sequence</a>
%H A209234 Reinhard Zumkeller, <a href="/A209234/a209234.hs.txt">Haskell program for two-digit Look-and-Say sequences</a>
%e A209234 a(0) = 10: 1x10 --> a(1)=110;
%e A209234 a(1) = 110: 1x10 and 1x11 --> a(2)=110111;
%e A209234 a(2) = 110111: 1x01, 1x10 and 3x11 -> a(3)=101110311;
%e A209234 a(3) = 101110311: 1x01, 1x03, 2x10, 3x11 and 1x31 -> a(4)=101103210311131.
%o A209234 (Haskell) -- See Link.
%Y A209234 Cf. A005151, A047842, A001155.
%Y A209234 Cf. A209233 (start=11), A221368 (start=12), A221369 (start=13), A221372 (start=19), A221373 (start=99).
%K A209234 nonn,base,look
%O A209234 0,1
%A A209234 _Reinhard Zumkeller_, Jan 13 2013