login
This site is supported by donations to The OEIS Foundation.

 

Logo

Annual appeal: Please make a donation to keep the OEIS running! Over 6000 articles have referenced us, often saying "we discovered this result with the help of the OEIS".
Other ways to donate

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A164408 Number of binary strings of length n with no substrings equal to 0000 0001 or 0011. 1
13, 23, 40, 68, 118, 203, 349, 602, 1036, 1784, 3073, 5291, 9112, 15692, 27022, 46535, 80137, 138002, 237652, 409256, 704773, 1213679, 2090056, 3599252, 6198214, 10673843, 18381253, 31654058, 54510940, 93872408, 161656153, 278385443 (list; graph; refs; listen; history; text; internal format)
OFFSET

4,1

LINKS

R. H. Hardin, Table of n, a(n) for n=4..500

Index entries for linear recurrences with constant coefficients, signature (1, 1, 1, -1).

FORMULA

G.f.: x^4*(13+10*x+4*x^2-8*x^3) / ( 1-x-x^2-x^3+x^4 ). - R. J. Mathar, Nov 28 2011

MATHEMATICA

CoefficientList[Series[(13 + 10*x + 4*x^2 - 8*x^3)/(1 - x - x^2 - x^3 + x^4), {x, 0, 50}], x] (* Wesley Ivan Hurt, Jan 10 2017 *)

LinearRecurrence[{1, 1, 1, -1}, {13, 23, 40, 68}, 50] (* G. C. Greubel, Sep 19 2017 *)

PROG

(PARI) x='x+O('x^50); Vec(x^4*(13+10*x+4*x^2-8*x^3)/(1-x-x^2-x^3+x^4)) \\ G. C. Greubel, Sep 19 2017

CROSSREFS

Sequence in context: A089714 A070219 A046119 * A164416 A164491 A164434

Adjacent sequences:  A164405 A164406 A164407 * A164409 A164410 A164411

KEYWORD

nonn

AUTHOR

R. H. Hardin, Aug 14 2009

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy .

Last modified November 18 05:08 EST 2017. Contains 294853 sequences.