Search: id:A014578 Results 1-1 of 1 results found. %I A014578 %S A014578 0,1,1,0,1,1,0,1,1,1,1,1,0,1,1,0,1,1,1,1,1,0,1,1,0,1,1,0,1,1,0,1,1, %T A014578 0,1,1,1,1,1,0,1,1,0,1,1,1,1,1,0,1,1,0,1,1,0,1,1,0,1,1,0,1,1,1,1,1, %U A014578 0,1,1,0,1,1,1,1,1,0,1,1,0,1,1,1,1,1,0,1,1,0,1,1,1,1,1,0,1,1,0,1,1 %N A014578 Binary expansion of Thue constant (or Roth's constant). %C A014578 a(0)=0; to construct the sequence start with a(1)=1, then concatenate twice and change the last term 1->0 giving 1,1,0. Concatenate those 3 terms twice giving 1,1,0,1,1,0,1,1,0, change the last term 0->1 giving 1,1,0,1,1,0,1,1,1. Concatenate those 9 terms twice and change the last term 1->0 etc. - Benoit Cloitre (benoit7848c(AT)orange.fr), Feb 09 2003 %C A014578 Bill Gosper, Mar 19 2004: It is probably my fault if this constant is misattributed. It was "computed" circa 1971 by a very simple Life pattern (as a diagonal row of blinkers), an obvious case of the (Thue-Siegel-)Roth criterion for transcendence, since the error after 3^n bits is ~2^-3^(n+1) = O(denominator^-3). I probably should have called it Roth's constant. %C A014578 a(0) = 0; then fixed point of the morphism 1->110, 0->111, starting with a(1) = 1 . - DELEHAM Philippe (kolotoko(AT)wanadoo.fr), Mar 21 2004 %C A014578 Characteristic function of A007417, i.e. a(n) = 1 if n is in A007417 and a(n) = 0 otherwise . - DELEHAM Philippe (kolotoko(AT)wanadoo.fr), Mar 21 2004 %C A014578 Multiplicative with a(3^e) = (e+1)%2, a(p^e) = 1 otherwise. David W. Wilson (davidwwilson(AT)comcast.net) Jun 10, 2005. %C A014578 a(A145204(n)) = 0, a(A007417(n)) = 1. [From Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Oct 04 2008] %H A014578 Index entries for characteristic functions %H A014578 Joerg Arndt, Fxtbook %H A014578 Michael Gilleland, Some Self-Similar Integer Sequences %H A014578 Eric Weisstein's World of Mathematics, Link to a section of The World of Mathematics. %H A014578 Eric Weisstein's World of Mathematics, Thue Constant %F A014578 a(0)=0; for n>=1, a(n)=sum(k>=0, (-1)^k*(floor(n/3^k)-floor((n-1)/3^k))) - Benoit Cloitre (benoit7848c(AT)orange.fr), Jun 03 2003 %F A014578 a(0)=0, a(3k)=1-a(k); a(3k+1)=a(3k+2)=1. - Benoit Cloitre (benoit7848c(AT)orange.fr), Mar 19 2004 %F A014578 Sum_{k=0..3^n} a(k) = A015518(n+1) = (-1)^n*A014983(n+1). - DELEHAM Philippe (kolotoko(AT)wanadoo.fr), Mar 31 2004 %F A014578 a(n) = 1 - A007949(n) mod 2 for n>0. [From Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Oct 04 2008] %t A014578 Nest[ Flatten[ # /. {0 -> {1, 1, 1}, 1 -> {1, 1, 0}}] &, {0}, 5] (from Robert G. Wilson v Mar 09 2005) %o A014578 (PARI) a(n)=if(n<1,0,sum(k=0,ceil(log(n)/log(3)),(-1)^k*(floor(n/3^k)-floor((n-1)/ 3^k)))) %Y A014578 Cf. Thue-Morse or parity constant A010060. %Y A014578 Sequence in context: A000494 A022933 A163532 this_sequence A030190 A157658 A123506 %Y A014578 Adjacent sequences: A014575 A014576 A014577 this_sequence A014579 A014580 A014581 %K A014578 nonn,cons,mult %O A014578 0,1 %A A014578 Eric Weisstein (eric(AT)weisstein.com) Search completed in 0.002 seconds