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A164443
Number of binary strings of length n with no substrings equal to 0000, 0111 or 1110.
1
1, 2, 4, 8, 13, 22, 37, 64, 110, 190, 329, 570, 988, 1713, 2971, 5153, 8938, 15504, 26894, 46652, 80926, 140381, 243517, 422426, 732778, 1271143, 2205040, 3825063, 6635303, 11510202, 19966647, 34635969, 60082715, 104224965, 180798144, 313628975, 544049468
OFFSET
0,2
LINKS
Alois P. Heinz, Table of n, a(n) for n = 0..2000 (terms n = 4..500 from R. H. Hardin)
FORMULA
G.f.: -(x^8+2*x^7+3*x^6+2*x^5+x^4-x^3-x^2-x-1) / ( (x-1)*(x^5+2*x^4+2*x^3+x^2-1) ). - R. J. Mathar, Jan 19 2011
CROSSREFS
Sequence in context: A164507 A164414 A164411 * A074467 A018066 A164509
KEYWORD
nonn,easy
AUTHOR
R. H. Hardin, Aug 14 2009
EXTENSIONS
a(0)-a(3) prepended by Alois P. Heinz, Apr 03 2024
STATUS
approved