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A164316
Number of binary strings of length n with no substrings equal to 000, 001, or 010.
3
1, 2, 4, 5, 7, 11, 16, 23, 34, 50, 73, 107, 157, 230, 337, 494, 724, 1061, 1555, 2279, 3340, 4895, 7174, 10514, 15409, 22583, 33097, 48506, 71089, 104186, 152692, 223781, 327967, 480659, 704440, 1032407, 1513066, 2217506, 3249913, 4762979, 6980485, 10230398
OFFSET
0,2
LINKS
Alois P. Heinz, Table of n, a(n) for n = 0..2000 (first 500 terms from R. H. Hardin)
Dominika Závacká, Cristina Dalfó, and Miquel Angel Fiol, Integer sequences from k-iterated line digraphs, CEUR: Proc. 24th Conf. Info. Tech. - Appl. and Theory (ITAT 2024) Vol 3792, 156-161. See p. 161, Table 2.
FORMULA
G.f.: -(2*x^2+x+1)/(x^3+x-1). - R. J. Mathar, Nov 28 2011
a(n) = 4 + Sum_{i=0..n-3} a(i) for n>2. - Greg Dresden, Jul 02 2021
EXAMPLE
All solutions for n=6: 101100 101101 101110 101111 011011 011100 011101 011110 011111 111011 110110 110111 111100 111101 111110 111111.
MATHEMATICA
LinearRecurrence[{1, 0, 1}, {1, 2, 4}, 80] (* Vladimir Joseph Stephan Orlovsky, Feb 15 2012, edited by Greg Dresden, Jul 02 2021 *)
CROSSREFS
Sequence in context: A050134 A010065 A344654 * A323146 A250006 A257033
KEYWORD
easy,nonn
AUTHOR
R. H. Hardin, Aug 12 2009
EXTENSIONS
Edited by Alois P. Heinz, Oct 11 2017
STATUS
approved