login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A164418
Number of binary strings of length n with no substrings equal to 0000 0010 or 0101
1
13, 22, 38, 66, 115, 200, 347, 601, 1042, 1808, 3137, 5442, 9440, 16375, 28405, 49274, 85476, 148275, 257211, 446181, 773986, 1342627, 2329044, 4040173, 7008453, 12157502, 21089513, 36583796, 63461595, 110086280, 190965717, 331266576
OFFSET
4,1
FORMULA
G.f.: -x^4*(13+9*x+16*x^2+15*x^3+14*x^4+12*x^5+8*x^6) / ( (x^2-x+1)*(x^5+2*x^4+2*x^3+x^2-1) ). - R. J. Mathar, Nov 30 2011
CROSSREFS
Sequence in context: A164421 A164493 A164445 * A301788 A164409 A301962
KEYWORD
nonn
AUTHOR
R. H. Hardin Aug 14 2009
STATUS
approved