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%I #9 Nov 14 2018 17:07:02
%S 1,11,21,121,1121,21121,121121,2121,221,2211,2221,3211,13211,113211,
%T 2113211,12113211,112113211,2112113211,221113211,223113211,2213113211,
%U 22113113211,2221131211,3221131211,13221131211,113221131211,2113221131211,12113221131211
%N a(1) = 1 and for any n > 1, a(n) = A321485(a(n-1)).
%C This sequence is a variant of the Look and Say sequence A005150; here we use A321485 instead of A045918 to describe the previous term.
%C In contrast to A005150, this sequence is not monotonic.
%C The first digit 1 appear in a(1) = 1.
%C The first digit 2 appear in a(3) = 21.
%C The first digit 3 appear in a(12) = 3211.
%C The first digit 4 appear in a(288) = 2221134231131131211.
%C Will other digits also appear?
%C Is this sequence bounded?
%H Rémy Sigrist, <a href="/A321509/b321509.txt">Table of n, a(n) for n = 1..10000</a>
%H Rémy Sigrist, <a href="/A321509/a321509.txt">C++ program for A321509</a>
%e The first terms, alongside the corresponding blocks, are:
%e n a(n) Blocks
%e -- ---------- ------------------
%e 1 1 (1)
%e 2 11 (1|1)
%e 3 21 (21)
%e 4 121 (121)
%e 5 1121 (1|1)(21)
%e 6 21121 (21121)
%e 7 121121 (121|121)
%e 8 2121 (21|21)
%e 9 221 (2|2)(1)
%e 10 2211 (2|2)(1|1)
%e 11 2221 (2|2|2)(1)
%e 12 3211 (3211)
%e 13 13211 (13211)
%e 14 113211 (1|1)(3211)
%e 15 2113211 (2113211)
%e 16 12113211 (12113211)
%e 17 112113211 (1|1)(2113211)
%e 18 2112113211 (211|211)(3211)
%e 19 221113211 (2|2)(1|1|1)(3211)
%e 20 223113211 (2|2)(3113211)
%o (C++) See Links section.
%Y Cf. A005150, A045918, A321485.
%K nonn,base
%O 1,2
%A _Rémy Sigrist_, Nov 11 2018