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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A164393 Number of binary strings of length n with no substrings equal to 0001 or 0011. 1
1, 2, 4, 8, 14, 25, 44, 76, 132, 228, 393, 678, 1168, 2012, 3466, 5969, 10280, 17704, 30488, 52504, 90417, 155706, 268140, 461760, 795190, 1369385, 2358196, 4061012, 6993404, 12043228, 20739449, 35715070, 61504344, 105915636, 182395602, 314100513 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

R. H. Hardin, Table of n, a(n) for n = 0..500

Index entries for linear recurrences with constant coefficients, signature (2,0,0,-2,1).

FORMULA

a(n) = 2*a(n-1) - 2*a(n-4) + a(n-5). - Andrew Howroyd, Feb 14 2018

G.f.: 1/((1 - x)*(1 - x - x^2 - x^3 + x^4)). - R. J. Mathar, Dec 01 2011

MATHEMATICA

LinearRecurrence[{2, 0, 0, -2, 1}, {1, 2, 4, 8, 14}, 50] (* G. C. Greubel, Sep 18 2017 *)

PROG

(PARI) Vec(1/((1 - x)*(1 - x - x^2 - x^3 + x^4)) + O(x^40)) \\ G. C. Greubel, Sep 18 2017

CROSSREFS

Sequence in context: A291443 A210145 A020956 * A164391 A164153 A212588

Adjacent sequences:  A164390 A164391 A164392 * A164394 A164395 A164396

KEYWORD

nonn

AUTHOR

R. H. Hardin, Aug 14 2009

EXTENSIONS

a(0)-a(3) prepended by Andrew Howroyd, Feb 14 2018

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 17 14:18 EST 2018. Contains 317276 sequences. (Running on oeis4.)