login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo

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 56th year, we are closing in on 350,000 sequences, and we’ve crossed 9,700 citations (which often say “discovered thanks to the OEIS”).

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A005595 States of a dynamic storage system.
(Formerly M1069)
1
1, 2, 4, 7, 13, 23, 46, 88, 186, 395, 880, 1989, 4644, 10934, 26210, 63319, 154377, 378443, 933022, 2308956, 5735371, 14286907, 35683814, 89324137, 224057918, 563033978, 1417210456, 3572641303, 9018885121, 22796905055, 57692673962, 146167385344, 370710166434 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

REFERENCES

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

LINKS

Andrew Howroyd, Table of n, a(n) for n = 0..200

C. G. Bower, Transforms

M. D. McIlroy, The number of states of a dynamic storage system, Computer J., 25 (No. 3, 1982), 388-392.

M. D. McIlroy, The number of states of a dynamic storage system, Computer J., 25 (No. 3, 1982), 388-392. (Annotated scanned copy)

Index entries for sequences related to bracelets

FORMULA

Also "DIK" (bracelet, indistinct, unlabeled) transform of 2, 1, 1, 1, ...

G.f.: ((2 - 2*x + x^3)/((1 - x)*(1 - x - x^2)) + Sum_{d>0} phi(d)*log((1-x^d)/(1-3*x^d+x^(2*d)))/d)/2. - Andrew Howroyd, Jun 20 2018

PROG

(PARI) seq(n)={Vec((2 - 2*x + x^3)/((1 - x)*(1 - x - x^2)) + sum(d=1, n, eulerphi(d)/d*log((1-x^d)/(1-3*x^d+x^(2*d)) + O(x*x^n))))/2} \\ Andrew Howroyd, Jun 20 2018

CROSSREFS

Sequence in context: A093629 A174566 A018182 * A296689 A327543 A096236

Adjacent sequences:  A005592 A005593 A005594 * A005596 A005597 A005598

KEYWORD

nonn

AUTHOR

N. J. A. Sloane

EXTENSIONS

Sequence extended by Christian G. Bower

Terms a(30) and beyond from Andrew Howroyd, Jun 20 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
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified December 6 16:26 EST 2021. Contains 349567 sequences. (Running on oeis4.)