Search: id:A005267 Results 1-1 of 1 results found. %I A005267 M2248 %S A005267 3,2,5,29,869,756029,571580604869,326704387862983487112029, %T A005267 106735757048926752040856495274871386126283608869, %U A005267 11392521832807516835658052968328096177131218666695418950023483907701862019030266123104859068029 %N A005267 a(n) = -1 + a(0)a(1)...a(n-1) if n>0. a(0)=3. %C A005267 An infinite coprime sequence defined by recursion. - Michael Somos Mar 14 2004 %C A005267 Let u(k), v(k) be defined by u(1)=1, v(1)=3, u(k+1)=v(k)-u(k), v(k+1)=u(k)v(k); then a(n)=v(2n) - Benoit Cloitre (benoit7848c(AT)orange.fr), Apr 02 2002 %C A005267 For positive n, a(n) has digital root 2 or 5 depending on whether n is odd or even.(T.Koshy). - Lekraj Beedassy (blekraj(AT)yahoo.com), Apr 11 2005 %D A005267 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). %D A005267 R. K. Guy and R. Nowakowski, ``Discovering primes with Euclid,'' Delta (Waukesha), Vol. 5, pp. 49-63, 1975. %D A005267 T. Koshy, "Intriguing Properties Of Three Related Number Sequences", in Journal of Recreational Mathematics, Vol. 32(3) pp. 210-213, 2003-2004 Baywood NY. %F A005267 a(n) = -1 + a(0)a(1)...a(n-1). %F A005267 a(n) = -1 + product_{i1. a(0)=3, a(1)=2. %F A005267 An induction shows that a(n+1) = A117805(n) - 1. - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Apr 22 2007; M. F. Hasler (maximilian.hasler(AT)gmail.com), May 04 2007. %F A005267 For n>0, a(n) = a(0)^2 + a(1)^2 + ... + a(n-1)^2 - n - 6. - Max Alekseyev (maxale(AT)gmail.com), Jun 19 2008 %o A005267 (PARI) a(n)=if(n<2,3*(n>=0)-(n>0),a(n-1)^2+a(n-1)-1) %Y A005267 Cf. A000058, A000289, A117805. %Y A005267 Sequence in context: A085973 A005265 A005266 this_sequence A016460 A097887 A019761 %Y A005267 Adjacent sequences: A005264 A005265 A005266 this_sequence A005268 A005269 A005270 %K A005267 easy,nonn %O A005267 0,1 %A A005267 N. J. A. Sloane (njas(AT)research.att.com). %E A005267 The next term is too large to include. Search completed in 0.001 seconds