cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A093371 Start with any initial string of n numbers s(1), ..., s(n), with s(1) = 2, other s(i)'s = 2 or 3 (so there are 2^(n-1) starting strings). The rule for extending the string is this as follows: To get s(n+1), write the string s(1)s(2)...s(n) as xy^k for words x and y (where y has positive length) and k is maximized, i.e., k = the maximal number of repeating blocks at the end of the sequence. Then a(n) = number of starting strings for which k = 1.

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%I A093371 #31 Jul 28 2017 23:45:25
%S A093371 1,1,2,3,6,10,20,37,74,143,286,562,1124,2230,4460,8884,17768,35465,
%T A093371 70930,141720,283440,566600,1133200,2265843,4531686,9062261,18124522,
%U A093371 36246826,72493652,144982872
%N A093371 Start with any initial string of n numbers s(1), ..., s(n), with s(1) = 2, other s(i)'s = 2 or 3 (so there are 2^(n-1) starting strings). The rule for extending the string is this as follows: To get s(n+1), write the string s(1)s(2)...s(n) as xy^k for words x and y (where y has positive length) and k is maximized, i.e., k = the maximal number of repeating blocks at the end of the sequence. Then a(n) = number of starting strings for which k = 1.
%C A093371 See A122536 for many more terms. - _N. J. A. Sloane_, Oct 25 2012
%H A093371 F. J. van de Bult, D. C. Gijswijt, J. P. Linderman, N. J. A. Sloane and Allan Wilks, <a href="http://www.cs.uwaterloo.ca/journals/JIS/index.html">A Slow-Growing Sequence Defined by an Unusual Recurrence</a>, J. Integer Sequences, Vol. 10 (2007), #07.1.2.
%H A093371 F. J. van de Bult, D. C. Gijswijt, J. P. Linderman, N. J. A. Sloane and Allan Wilks, A Slow-Growing Sequence Defined by an Unusual Recurrence [<a href="http://neilsloane.com/doc/gijs.pdf">pdf</a>, <a href="http://neilsloane.com/doc/gijs.ps">ps</a>].
%H A093371 <a href="/index/Cu#curling_numbers">Index entries for sequences related to curling numbers</a>
%F A093371 a(n) = 2^(n-1) - A093370(n).
%Y A093371 Cf. A093370, A093369, A090822, A216955, A216956.
%Y A093371 Equals A122536/2. - _N. J. A. Sloane_, Sep 25 2012
%Y A093371 Different from, but easily confused with, A007148 and A045690.
%K A093371 nonn
%O A093371 1,3
%A A093371 _N. J. A. Sloane_, Apr 28 2004
%E A093371 More terms from _N. J. A. Sloane_, Sep 26 2012