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A281193 Elias's omega code for n.

%I A281193 #26 Feb 12 2025 18:45:03
%S A281193 0,100,110,101000,101010,101100,101110,1110000,1110010,1110100,
%T A281193 1110110,1111000,1111010,1111100,1111110,10100100000,10100100010,
%U A281193 10100100100,10100100110,10100101000,10100101010,10100101100,10100101110,10100110000,10100110010,10100110100
%N A281193 Elias's omega code for n.
%C A281193 The idea of the Elias omega code is similar to that of the Elias delta code (A281150), except that the length of the codeword in the omega code is recursively encoded.
%C A281193 The number of bits in a(n) is equal to A072464(n).
%H A281193 Indranil Ghosh, <a href="/A281193/b281193.txt">Table of n, a(n) for n = 1..10000</a>
%H A281193 Khalid Sayood (Editor), <a href="https://books.google.co.in/books?id=LjQiGwyabVwC&amp;pg=PA60&amp;lpg=PA60&amp;dq=bl&amp;ots=DEU6sh5UC9&amp;sig=GJcMAaVWdAH1pQ4LYNyZVaMUlRM&amp;hl=en&amp;sa=X&amp;ved=0ahUKEwjzq7ulvcfRAhVJRo8KHbNUC1QQ6AEIITAB#v=onepage&amp;q=Even%20Rodeh&amp;f=false">Lossless Compression Handbook</a>, Chapter 3 - Universal Codes, p. 59, section 3.6.
%H A281193 Wikipedia, <a href="https://en.wikipedia.org/wiki/Elias_omega_coding">Elias omega coding</a>
%o A281193 (Python)
%o A281193 def E(n):
%o A281193     s=""
%o A281193     if n==1:
%o A281193         return "0"
%o A281193     else:
%o A281193         b=(bin(n)[2:])
%o A281193         s+=E(len(b)-1)+b
%o A281193     return s
%o A281193 def elias_omega(n):
%o A281193     return int(E(n)[1:]+"0")
%Y A281193 Cf. A072464, A281149, A281150.
%K A281193 nonn,base
%O A281193 1,2
%A A281193 _Indranil Ghosh_, Jan 17 2017