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A154999 a(n)=7*a(n-1)+42*a(n-2), n>2 ; a(0)=1, a(1)=1, a(2)=13 . 2
1, 1, 13, 133, 1477, 15925, 173509, 1883413, 20471269, 222402229, 2416608901, 26257155925, 285297665317, 3099884206069, 33681691385797, 365966976355477, 3976399872691813, 43205412115772725, 469446679463465221 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Table of n, a(n) for n=0..18.

FORMULA

a(n+1)=Sum_{k, 0<=k<=n}A154929(n,k)*6^(n-k).

a(n)=(19/434)*sqrt(217)*{[(7/2)+(1/2)*sqrt(217)]^(n-1)-[(7/2)-(1/2)*sqrt(217)]^(n-1)} +(1/2)*{[(7/2)+(1/2)*sqrt(217)]^(n-1)+[(7/2)-(1/2)*sqrt(217)]^(n-1)}+(6/7)*[C(2*n,n) mod 2], with n>=0 [From Paolo P. Lava, Jan 20 2009]

CROSSREFS

Sequence in context: A031138 A097166 A073556 * A228277 A221153 A262572

Adjacent sequences:  A154996 A154997 A154998 * A155000 A155001 A155002

KEYWORD

nonn

AUTHOR

Philippe Deléham, Jan 18 2009

EXTENSIONS

More terms from Philippe Deléham, Jan 27 2009

Corrected by D. S. McNeil, Aug 20 2010

STATUS

approved

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Last modified March 26 06:49 EDT 2017. Contains 284111 sequences.