Search: id:A016031 Results 1-1 of 1 results found. %I A016031 %S A016031 1,1,2,16,2048,67108864,144115188075855872, %T A016031 1329227995784915872903807060280344576, %U A016031 226156424291633194186662080095093570025917938800079226639565593765455331328 %N A016031 De Bruijn's sequence: 2^(2^(n-1) - n): ways of arranging 2^n bits in circle so all 2^n consecutive strings of length n are distinct. %C A016031 Sequence corresponds also to the largest number that may be determined by asking no more than 2^(n-1) - 1 questions("Yes"-or-"No" answerable)with lying allowed at most once. - Lekraj Beedassy (blekraj(AT)yahoo.com), Jul 15 2002 %C A016031 Number of Ouroborean rings for binary n-tuplets. - Lekraj Beedassy (blekraj(AT)yahoo.com), May 06 2004 %C A016031 Also the number of games of Nim that are wins for the second player when the starting position is either the empty heap or heaps of sizes 1 <= t_1 < t_2 < ... < t_k < 2^(n-1) (if n is 1, the only starting position is the empty heap). E.g.: a(4) = 16: the winning positions for the second player when all the heap sizes are different and less than 2^3: (4,5,6,7), (3,5,6), (3,4,7), (2,5,7), (2,4,6), (2,3,6,7), (2,3,4,5), (1,6,7), (1,4,5), (1,3,5,7), (1,3,4,6), (1,2,5,6), (1, 2,4,7), (1,2,3), (1,2,3,4,5,6,7) and the empty heap. - Kennan Shelton (kennan.shelton(AT)gmail.com), Apr 14 2006 %D A016031 F. Harary and E. Palmer, Graphical Enumeration, (1973), p. 31. %D A016031 D. J. Newman, "A variation of the Game of Twenty Question", Prob. 66-20 pp. 121-2 In Problems in Applied Mathematics, Ed. M. S. Klamkin, SIAM PA 1990. %D A016031 R. P. Stanley, Enumerative Combinatorics, Cambridge, Vol. 2, 1999; see Cor. 5.6.15. %D A016031 I. Stewart, Game, Set and Math, pp. 50, Penguin 1991. %D A016031 J. L. Gross and J. Yellen, eds., Handbook of Graph Theory, CRC Press, 2004; p. 255. %H A016031 R. Erra, N. Lygeros and N. Stewart, On Minimal Strings Containing the Elements of S(n) by Decimation; Section 5.4 %H A016031 Wikipedia, De Bruijn sequence %F A016031 a(n)=2^{A000295(n-1)}. - Lekraj Beedassy (blekraj(AT)yahoo.com), Jan 17 2007 %p A016031 P:=proc(n) local i,j; for i from 1 by 1 to n do j:=2^(2^(i-1)-i); print(j); od; end: P(20); - Paolo P. Lava (ppl(AT)spl.at), May 11 2006 %Y A016031 Sequence in context: A102103 A060597 A091479 this_sequence A001309 A132569 A165644 %Y A016031 Adjacent sequences: A016028 A016029 A016030 this_sequence A016032 A016033 A016034 %K A016031 nonn,easy,nice %O A016031 1,3 %A A016031 N. J. A. Sloane (njas(AT)research.att.com), Robert G. Wilson v (rgwv(AT)rgwv.com) Search completed in 0.001 seconds