Search: id:A001631 Results 1-1 of 1 results found. %I A001631 M1081 N0410 %S A001631 0,0,1,0,1,2,4,7,14,27,52,100,193,372,717,1382,2664,5135,9898,19079, %T A001631 36776,70888,136641,263384,507689,978602,1886316,3635991,7008598, %U A001631 13509507,26040412,50194508,96753025,186497452,359485397,692930382 %N A001631 Tetranacci numbers: a(n) = a(n-1) + a(n-2) + a(n-3) +a(n-4). %D A001631 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). %D A001631 N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence). %D A001631 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 A001631 W. C. Lynch, The t-Fibonacci numbers and polyphase sorting, Fib. Quart., 8 (1970), pp. 6ff. %H A001631 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 A001631 S. Plouffe, 1031 Generating Functions and Conjectures, Universit\'{e} du Qu\'{e}bec \`{a} Montr\'{e}al, 1992. %p A001631 A001631:=(-1+z)/(-1+z+z**2+z**3+z**4); [Conjectured by S. Plouffe in his 1992 dissertation.] %p A001631 (Maple) a := n -> (Matrix([[0,-1,2,-1]]). Matrix(4, (i,j)-> if (i=j-1) or j=1 then 1 else 0 fi)^n)[1,1] ; seq (a(n), n=0..35); [From Alois P. Heinz (heinz(AT)hs-heilbronn.de), Aug 01 2008] %Y A001631 First differences of A000078. %Y A001631 Sequence in context: A005594 A123196 A079968 this_sequence A108758 A018085 A167751 %Y A001631 Adjacent sequences: A001628 A001629 A001630 this_sequence A001632 A001633 A001634 %K A001631 nonn,easy %O A001631 0,6 %A A001631 N. J. A. Sloane (njas(AT)research.att.com). %E A001631 More terms from Larry Reeves (larryr(AT)acm.org), Jul 31 2000 Search completed in 0.001 seconds