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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A134863 Wythoff BAB numbers. 9
7, 20, 28, 41, 54, 62, 75, 83, 96, 109, 117, 130, 143, 151, 164, 172, 185, 198, 206, 219, 227, 240, 253, 261, 274, 287, 295, 308, 316, 329, 342, 350, 363, 376, 384, 397, 405, 418, 431, 439, 452, 460, 473, 486, 494, 507, 520, 528, 541, 549, 562, 575, 583, 596 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The lower and upper Wythoff sequences, A and B, satisfy the complementary equation BAB=2A+3B-1.

LINKS

Table of n, a(n) for n=1..54.

Clark Kimberling, Complementary equations and Wythoff Sequences, Journal of Integer Sequences 11 (2008) Article 08.3.3.

FORMULA

a(n) = B(A(B(n))), n>=1, with A=A000201, the lower Wythoff sequence and B=A001950, the upper Wythoff sequence.

PROG

(Python)

from sympy import floor

from mpmath import phi

def A(n): return floor(n*phi)

def B(n): return floor(n*phi**2)

def a(n): return B(A(B(n))) # Indranil Ghosh, Jun 10 2017

CROSSREFS

Cf. A000201, A001950, A003622, A003623, A035336, A101864, A134859, A035337, A134860, A134861, A134862, A035338, A134864, A035513.

Let A = A000201, B = A001950. Then AA = A003622, AB = A003623, BA = A035336, BB = A101864. The eight triples AAA, AAB, ..., BBB are A134859, A134860, A035337, A134862, A134861, A134863, A035338, A134864, resp.

Sequence in context: A070413 A015243 A055069 * A214924 A319966 A200773

Adjacent sequences:  A134860 A134861 A134862 * A134864 A134865 A134866

KEYWORD

nonn

AUTHOR

Clark Kimberling, Nov 14 2007

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 October 20 07:17 EDT 2018. Contains 316378 sequences. (Running on oeis4.)