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A081013 Fibonacci(4n+3)-2, or Fibonacci(2n)*Lucas(2n+3). 0
0, 11, 87, 608, 4179, 28655, 196416, 1346267, 9227463, 63245984, 433494435, 2971215071, 20365011072, 139583862443, 956722026039, 6557470319840, 44945570212851, 308061521170127, 2111485077978048, 14472334024676219 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

REFERENCES

Hugh C. Williams, Edouard Lucas and Primality Testing, John Wiley and Sons, 1998, p. 75

LINKS

Index to sequences with linear recurrences with constant coefficients, signature (8,-8,1). [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Sep 03 2010]

FORMULA

a(n) = 8a(n-1)-8a(n-2)+a(n-3)

a(n)=-2+[(7/2)-(3/2)*sqrt(5)]^n+[(7/2)+(3/2)*sqrt(5)]^n+(2/5)*sqrt(5)*[(7/2)+(3/2)*sqrt(5)]^n-[(7/2)-(3/2)*sqrt(5)]^n}, with n>=0 [From Paolo P. Lava (paoloplava(AT)gmail.com), Dec 01 2008]

G.f.: x*(-11+x) / ( (x-1)*(x^2-7*x+1) ). a(n) = A033891(n)-2. a(n+1)-a(n) = A056914(n+1), n>0. [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Sep 03 2010]

MAPLE

with(combinat) for n from 0 to 25 do printf(`%d, `, fibonacci(4*n+3)-2) od

PROG

(MAGMA) [Fibonacci(4*n+3)-2: n in [0..50]]; // Vincenzo Librandi, Apr 20 2011

CROSSREFS

Cf. A000045 (Fibonacci numbers), A000032 (Lucas numbers).

Sequence in context: A014917 A080962 A016222 * A163616 A119383 A001278

Adjacent sequences:  A081010 A081011 A081012 * A081014 A081015 A081016

KEYWORD

nonn,easy

AUTHOR

R. K. Guy (rkg(AT)cpsc.ucalgary.ca), Mar 01, 2003

EXTENSIONS

More terms and Maple code from James A. Sellers (sellersj(AT)math.psu.edu), Mar 03, 2003

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Last modified February 17 09:41 EST 2012. Contains 206009 sequences.