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A164416
Number of binary strings of length n with no substrings equal to 0000 0001 or 1111
1
13, 23, 40, 69, 120, 208, 361, 626, 1086, 1884, 3268, 5669, 9834, 17059, 29592, 51333, 89047, 154469, 267956, 464821, 806321, 1398718, 2426344, 4208958, 7301243, 12665403, 21970565, 38112149, 66112815, 114685328, 198943646, 345105821
OFFSET
4,1
FORMULA
G.f.: -x^4*(13+23*x+27*x^2+20*x^3+8*x^4) / ( -1+x^2+2*x^3+2*x^4+x^5 ). - R. J. Mathar, Nov 30 2011
CROSSREFS
Sequence in context: A070219 A046119 A374102 * A164491 A164434 A164494
KEYWORD
nonn
AUTHOR
R. H. Hardin Aug 14 2009
STATUS
approved