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A123394 Sequence allows us to find X values of the equation: 7(X-Y)^4-8XY=0 with X>=Y. 0
0, 64, 54000, 48387776, 43449047520, 39017102749504, 35037312017058000, 31463467090220398016, 28254158407188855215040, 25372202786113074403284544, 22784209847768873321556750000 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

COMMENTS

Sequence gives X values. To find Y values: b(n)=c(n)*(-1+d(n))which gives: 0,56,53760,48380584,43448832000,

FORMULA

a(n)=c(n)*(1+d(n)) with c(0)=0,c(1)=4 and c(n)=30*c(n-1)-c(n-2) d(0)=1,d(1)=15 and d(n)=30*d(n-1)-d(n-2)

Contribution from Max Alekseyev (maxale(AT)gmail.com), Nov 13 2009: (Start)

a(n) = 2*A123393(n)

For n>=4, a(n) = 928*a(n-1) - 26942*a(n-2) + 928*a(n-3) - a(n-4)

o.g.f.: 16*x*(4*x^2-337*x+4)/(x^2-30*x+1)/(x^2-898*x+1) (End)

CROSSREFS

Sequence in context: A141092 A016830 A103346 * A069445 A159677 A013832

Adjacent sequences:  A123391 A123392 A123393 * A123395 A123396 A123397

KEYWORD

nonn

AUTHOR

Mohamed Bouhamida (bhmd95(AT)yahoo.fr), Oct 14 2006

EXTENSIONS

More terms from Max Alekseyev (maxale(AT)gmail.com), Nov 13 2009

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Last modified February 14 22:22 EST 2012. Contains 205678 sequences.