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Self-describing sequence made of strings of consecutive integers. The number of elements in each string is the sequence itself.
3

%I #10 Feb 08 2017 22:07:13

%S 1,3,4,5,1,2,3,4,1,2,3,4,5,1,3,4,1,2,3,1,2,3,4,1,3,4,1,2,3,1,2,3,4,1,

%T 2,3,4,5,1,3,4,5,1,2,3,4,1,3,4,1,2,3,1,3,4,1,2,3,1,2,3,4,1,3,4,5,1,2,

%U 3,4,1,3,4,1,2,3,1,3,4,1,2,3,1,2,3,4,1

%N Self-describing sequence made of strings of consecutive integers. The number of elements in each string is the sequence itself.

%C The less interesting sequence 1,1,1,1,1,1,1,1, ... obeys the same rule.

%H Rémy Sigrist, <a href="/A113138/b113138.txt">Table of n, a(n) for n = 1..1000</a>

%H Rémy Sigrist, <a href="/A113138/a113138.gp.txt">PARI program for A113138</a>

%e First string is "1", having 1 element. Second string is "3,4,5" having 3 elements. Third string is "1,2,3,4" which has 4 elements. Next string is "1,2,3,4,5", made of 5 elements. Next string is "1", having only 1 element, etc. So we have 1 element, then 3, then 4, then 5, then 1, etc. This is the sequence itself.

%Y Cf. A281579.

%K easy,nonn,nice

%O 1,2

%A _Eric Angelini_, Jan 04 2006

%E More terms from _Rémy Sigrist_, Feb 08 2017