Search: id:A006490 Results 1-1 of 1 results found. %I A006490 M2362 %S A006490 1,0,3,4,10,18,35,64,117,210,374,660,1157,2016,3495,6032,10370,17766, %T A006490 30343,51680,87801,148830,251758,425064,716425,1205568,2025675,3399004, %U A006490 5696122,9534330,15941099,26625280,44426877,74062506,123360230 %N A006490 a(1) = 1, a(2) = 0; for n >2, a(n)=n*Fibonacci(n-2) (with the convention Fibonacci(0)=0, Fibonacci(1)=1). %C A006490 Number of circular binary words of length n having exactly one occurrence of 00. Example: a(5)=10 because we have 00111, 10011, 11001, 11100, 01110, 00101, 10010, 01001, 10100 and 01010. Column 1 of A119458. - Emeric Deutsch (deutsch(AT)duke.poly.edu), May 20 2006 %D A006490 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). %D A006490 S. Plouffe, Approximations de S\'{e}ries G\'{e}n\'{e}ratrices et Quelques Conjectures, Dissertation, Universit\'{e} du Qu\'{e}bec \`{a} Montr\'{e}al, 1992. %D A006490 L. Carlitz and R. Scoville, Zero-one sequences and Fibonacci numbers, Fib. Quart., 15 (1977), 246-254. %D A006490 J. P. McSorley, Counting structures in the Moebius ladder, Discrete Math., 184 (1998), 137-164. %H A006490 S. Plouffe, Approximations de S\'{e}ries G\'{e}n\'{e}ratrices et Quelques Conjectures, Dissertation, Universit\'{e} du Qu\'{e}bec \`{a} Montr\'{e}al, 1992. %H A006490 S. Plouffe, 1031 Generating Functions and Conjectures, Universit\'{e} du Qu\'{e}bec \`{a} Montr\'{e}al, 1992. %F A006490 G.f.=x(1-2x+2x^2)/(1-x-x^2)^2. - Emeric Deutsch (deutsch(AT)duke.poly.edu), May 20 2006 %p A006490 with(combinat): a[1]:=1: a[2]:=0: for n from 3 to 40 do a[n]:=n*fibonacci(n-2) od: seq(a[n],n=1..40); - Emeric Deutsch (deutsch(AT)duke.poly.edu), May 20 2006 %p A006490 A006490:=(1-2*z+2*z**2)/(z**2+z-1)**2; [Conjectured by S. Plouffe in his 1992 dissertation.] %t A006490 Table[Sum[Fibonacci[n - 1], {i, 0, n}], {n, 0, 34}] [From Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Jul 12 2009] %Y A006490 Cf. A119458. %Y A006490 Sequence in context: A034774 A144958 A034775 this_sequence A139797 A036649 A109887 %Y A006490 Adjacent sequences: A006487 A006488 A006489 this_sequence A006491 A006492 A006493 %K A006490 nonn %O A006490 1,3 %A A006490 N. J. A. Sloane (njas(AT)research.att.com). %E A006490 Better definition from Ralf Stephan, Nov 18 2004 %E A006490 More terms from Emeric Deutsch (deutsch(AT)duke.poly.edu), May 20 2006 Search completed in 0.001 seconds