This site is supported by donations to The OEIS Foundation.

 Annual appeal: Please make a donation to keep the OEIS running! Over 6000 articles have referenced us, often saying "we discovered this result with the help of the OEIS". Other ways to donate

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A055850 a(n) = 3a(n-1) - a(n-2); a(0)=1, a(1)=10. 2
 1, 10, 29, 77, 202, 529, 1385, 3626, 9493, 24853, 65066, 170345, 445969, 1167562, 3056717, 8002589, 20951050, 54850561, 143600633, 375951338, 984253381, 2576808805, 6746173034, 17661710297, 46238957857, 121055163274 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 REFERENCES A. H. Beiler, Recreations in the Theory of Numbers, Dover, N.Y., 1964, pp. 194-196. LINKS Index entries for linear recurrences with constant coefficients, signature (3,-1). Tanya Khovanova, Recursive Sequences FORMULA a(n) = (10*(((3+sqrt(5))/2)^n - ((3-sqrt(5))/2)^n) - (((3+sqrt(5))/2)^(n-1) - ((3-sqrt(5))/2)^(n-1)))/sqrt(5). G.f.: (1+7*x)/(1-3*x+x^2). a(n) = Lucas(2n+1) + 6*Fibonacci(2n). PROG (MAGMA) [Lucas(2*n+1) + 6*Fibonacci(2*n): n in [0..30]]; // Vincenzo Librandi, Apr 18 2011 CROSSREFS Sequence in context: A048469 A031129 A048772 * A200185 A027979 A181102 Adjacent sequences:  A055847 A055848 A055849 * A055851 A055852 A055853 KEYWORD easy,nonn AUTHOR Barry E. Williams, Jun 03 2000 STATUS approved

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