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A041761 Denominators of continued fraction convergents to sqrt(401). 1
1, 40, 1601, 64080, 2564801, 102656120, 4108809601, 164455040160, 6582310416001, 263456871680200, 10544857177624001, 422057743976640240, 16892854616243233601, 676136242393705984280, 27062342550364482604801 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

LINKS

Tanya Khovanova, Recursive Sequences

FORMULA

a(n)=F(n, 40), the n-th Fibonacci polynomial evaluated at x=40. - T. D. Noe (noe(AT)sspectra.com), Jan 19 2006

a(n)=40*a(n-1)+a(n-2), n>1 ; a(0)=1, a(1)=40 . G.f.: 1/(1-40*x-x^2). [From Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Nov 23 2008]

MATHEMATICA

a=0; lst={}; s=0; Do[a=s-(a-1); AppendTo[lst, a]; s+=a*40, {n, 3*4!}]; lst [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Nov 03 2009]

CROSSREFS

Cf. A041760.

Sequence in context: A170759 A158703 A009984 * A140702 A145294 A147520

Adjacent sequences:  A041758 A041759 A041760 * A041762 A041763 A041764

KEYWORD

nonn,cofr,easy

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com).

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Last modified February 15 12:21 EST 2012. Contains 205785 sequences.