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 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) 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 EXTENSIONS Sequence extended by Christian G. Bower Terms a(30) and beyond from Andrew Howroyd, Jun 20 2018 STATUS approved

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