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 A281150 Elias delta code for n. 6
 1, 1000, 1001, 10100, 10101, 10110, 10111, 11000000, 11000001, 11000010, 11000011, 11000100, 11000101, 11000110, 11000111, 110010000, 110010001, 110010010, 110010011, 110010100, 110010101, 110010110, 110010111, 110011000, 110011001, 110011010 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS The number of bits in a(n) is equal to A140341(n). a(n) is the prefix-free encoding of n-1 defined on pages 180-181 of Shallit (2008). - N. J. A. Sloane, Mar 18 2019 REFERENCES Shallit, Jeffrey. A second course in formal languages and automata theory. Cambridge University Press, 2008. See E(m) on page 181. - N. J. A. Sloane, Mar 18 2019 LINKS Indranil Ghosh, Table of n, a(n) for n = 1..10000 J. Nelson Raja, P. Jaganathan and S. Domnic, A New Variable-Length Integer Code for Integer Representation and Its Application to Text Compression, Indian Journal of Science and Technology, Vol 8(24), September 2015. FORMULA For a given integer n, a(n) is composed of two parts. The first part equals 1+floor(log_2 n) and the second part equals n-2^(floor(log_2 n)). The first part is stored in Elias Gamma Code and the second part is stored in a binary using floor(log_2 n) bits. The first and the second parts are concatenated to give a(n). EXAMPLE For n = 9, the first part is "11000" and the second part is "001". So a(9) = 11000001. PROG (Python) def unary(n): ....return "1"*(n-1)+"0" def elias_gamma(n): ....if n==1: ........return "1" ....k=int(math.log(n, 2)) ....fp=unary(1+k)    #fp is the first part ....sp=n-2**(k)      #sp is the second part ....nb=k             #nb is the number of bits used to store sp in binary ....sp=bin(sp)[2:] ....if len(sp)

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Last modified May 14 09:14 EDT 2021. Contains 343879 sequences. (Running on oeis4.)