Search: id:A006355 Results 1-1 of 1 results found. %I A006355 %S A006355 1,0,2,2,4,6,10,16,26,42,68,110,178,288,466,754,1220,1974,3194,5168, %T A006355 8362,13530,21892,35422,57314,92736,150050,242786,392836,635622,1028458, %U A006355 1664080,2692538,4356618,7049156,11405774,18454930,29860704,48315634 %N A006355 Number of binary vectors of length n containing no singletons. %C A006355 Number of cvtemplates at n-2 letters given <= 2 consecutive consonants or vowels (n >= 4). %C A006355 Number of (n,2) Freiman-Wyner sequences. %C A006355 Diagonal sums of the Riordan array ((1-x+x^2)/(1-x), x/(1-x)), A072405 (where this begins 1,0,1,1,1,1,...). - Paul Barry (pbarry(AT)wit.ie), May 04 2005 %C A006355 a(n) = A119457(n-1,n-2) for n>2. - Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), May 20 2006 %D A006355 I. F. Blake, The enumeration of certain run length sequences, Information and Control, 55 (1982), 222-237. %D A006355 Enoch Haga, Room for Expansion, Word Ways, 33 (No. 2, 2000), pp. 106-113 (see p. 110). %D A006355 A. T. Benjamin and J. J. Quinn, Proofs that really count: the art of combinatorial proof, M.A.A. 2003, id. 16,51. %H A006355 Index entries for sequences related to linear recurrences with constant coefficients %H A006355 INRIA Algorithms Project, Encyclopedia of Combinatorial Structures 898 %F A006355 a(n+2) = F(n-1) + F(n+2), for n>0. %F A006355 G.f.: (1-x+x^2)/(1-x-x^2) - Paul Barry (pbarry(AT)wit.ie), May 04 2005 %p A006355 a := n-> if n=0 then 1 else (Matrix([[2,-2]]). Matrix([[1,1], [1,0]])^n)[1, 1] fi; seq (a(n), n=0..38); [From Alois P. Heinz (heinz(AT)hs-heilbronn.de), Aug 18 2008] %t A006355 lst={1};Do[AppendTo[lst,Fibonacci[n+3]-Fibonacci[n]],{n,-1,4*4!}];lst [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Jun 11 2009] %t A006355 lst={1};a=2;s=3;Do[a=s-(a+1);AppendTo[lst,a];s+=a,{n,5!}];lst [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Oct 27 2009] %Y A006355 Except for initial term, = 2*Fibonacci numbers (A000045). %Y A006355 Essentially the same as A055389. %Y A006355 Cf. A097925, A097926. %Y A006355 Essentially the same as A047992, A068922, A054886 and A090991. %Y A006355 Sequence in context: A139582 A034410 A050194 this_sequence A055389 A163733 A084202 %Y A006355 Adjacent sequences: A006352 A006353 A006354 this_sequence A006356 A006357 A006358 %K A006355 nonn,easy,nice %O A006355 0,3 %A A006355 David M. Bloom. %E A006355 More terms from Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), May 20 2006 %E A006355 Corrected by T. D. Noe (noe(AT)sspectra.com), Oct 31 2006 Search completed in 0.002 seconds