[go: up one dir, main page]

login
A090732
a(n) = 24a(n-1) - a(n-2), starting with a(0) = 2 and a(1) = 24.
3
2, 24, 574, 13752, 329474, 7893624, 189117502, 4530926424, 108553116674, 2600743873752, 62309299853374, 1492822452607224, 35765429562720002, 856877487052672824, 20529294259701427774, 491846184745781593752
OFFSET
0,1
FORMULA
a(n) = p^n + q^n, where p = 12 + sqrt(143) and q = 12 - sqrt(143). - Tanya Khovanova, Feb 06 2007
G.f.: (2-24*x)/(1-24*x+x^2). - Philippe Deléham, Nov 02 2008
a(n)=2*A077424(n). - R. J. Mathar, Sep 27 2014
MATHEMATICA
a[0] = 2; a[1] = 24; a[n_] := 24a[n - 1] - a[n - 2]; Table[ a[n], {n, 0, 15}] (* Robert G. Wilson v, Jan 30 2004 *)
LinearRecurrence[{24, -1}, {2, 24}, 30] (* Harvey P. Dale, Sep 19 2011 *)
PROG
(Sage) [lucas_number2(n, 24, 1) for n in range(0, 20)] # Zerinvary Lajos, Jun 26 2008
(PARI) a(n)=([0, 1; -1, 24]^n*[2; 24])[1, 1] \\ Charles R Greathouse IV, Feb 07 2017
CROSSREFS
Sequence in context: A377492 A377425 A170904 * A377427 A014298 A280794
KEYWORD
easy,nonn
AUTHOR
Nikolay V. Kosinov (kosinov(AT)unitron.com.ua), Jan 18 2004
STATUS
approved