This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A027831 Expansion of 1/(1-4*x+2*x^2+4*x^3-2*x^4). 1
 1, 4, 14, 44, 134, 400, 1184, 3488, 10252, 30096, 88296, 258960, 759368, 2226560, 6528256, 19140352, 56117392, 164528960, 482376160, 1414257856, 4146398048, 12156629760, 35641443840, 104495439360 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 LINKS Vincenzo Librandi, Table of n, a(n) for n = 0..1000 Index to sequences with linear recurrences with constant coefficients, signature (4,-2,-4,2) FORMULA a(n) = 4*a(n-1) -2*a(n-2) -4*a(n-3) +2*a(n-4). Vincenzo Librandi, Jun 20 2012 MATHEMATICA LinearRecurrence[{4, -2, -4, 2}, {1, 4, 14, 44}, 40] (* Vincenzo Librandi, Jun 20 2012 *) PROG (MAGMA) I:=[1, 4, 14, 44]; [n le 4 select I[n] else 4*Self(n-1)-2*Self(n-2)-4*Self(n-3)+2*Self(n-4): n in [1..40]]; // Vincenzo Librandi, Jun 20 2012 CROSSREFS Sequence in context: A094309 A000300 A005323 * A097894 A065835 A198643 Adjacent sequences:  A027828 A027829 A027830 * A027832 A027833 A027834 KEYWORD nonn,easy AUTHOR STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
Recent Additions | More pages | Superseeker | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .

Last modified May 23 12:58 EDT 2013. Contains 225588 sequences.