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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A052956 a(n) = 2^n + F_{n+1}. 0
2, 3, 6, 11, 21, 40, 77, 149, 290, 567, 1113, 2192, 4329, 8569, 16994, 33755, 67133, 133656, 266325, 531053, 1059522, 2114863, 4222961, 8434976, 16852241, 33675825, 67305282, 134535539, 268949685, 537702952, 1075088093, 2149661957 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

LINKS

Table of n, a(n) for n=0..31.

INRIA Algorithms Project, Encyclopedia of Combinatorial Structures 1027

FORMULA

G.f.: -(-2+3*x+x^2)/(-1+x+x^2)/(-1+2*x)

Recurrence: {a(2)=6, a(1)=3, a(0)=2, 2*a(n)+a(n+1)-3*a(n+2)+a(n+3)}

2^n+Sum(1/5*(1+2*_alpha)*_alpha^(-1-n), _alpha=RootOf(-1+_Z+_Z^2))

MAPLE

spec := [S, {S=Union(Sequence(Union(Prod(Z, Z), Z)), Sequence(Union(Z, Z)))}, unlabeled ]: seq(combstruct[count ](spec, size=n), n=0..20);

CROSSREFS

Cf. A000045, A000079.

Sequence in context: A109222 A191789 A006861 * A298118 A008930 A164362

Adjacent sequences:  A052953 A052954 A052955 * A052957 A052958 A052959

KEYWORD

easy,nonn

AUTHOR

encyclopedia(AT)pommard.inria.fr, Jan 25 2000

EXTENSIONS

More terms from James A. Sellers, Jun 05 2000

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
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified March 18 22:11 EDT 2019. Contains 321305 sequences. (Running on oeis4.)