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A147840 a(n)=10*a(n-1)-8*a(n-2), a(0)=1, a(1)=8 . 2
1, 8, 72, 656, 5984, 54592, 498048, 4543744, 41453056, 378180608, 3450181632, 31476371456, 287162261504, 2619811643392, 23900818341888, 218049690271744, 1989290355982336, 18148506037649408, 165570737528635392 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

a(n) = sum_{k=0..n} 2^n*binomial(n,k)*A007482(k) = 2^n*A052913(n). - R. J. Mathar, Oct 15 2012

LINKS

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

Index entries for linear recurrences with constant coefficients, signature (10,-8).

FORMULA

a(n)=Sum_{k, 0<=k<=n}A147703(n,k)*7^k . G.f.: (1-2x)/(1-10x+8*x^2).

a(n)=(1/2)*(5+sqrt(17))^n-(3/34)*sqrt(17)*[5-sqrt(17)]^n+(1/2)*[5-sqrt(17)]^n+(3/34)*[5 +sqrt(17)]^n*sqrt(17), with n>=0 [From Paolo P. Lava, Nov 18 2008]

a(n)= ((17+3*sqrt(17))/34)*(5+sqrt(17))^n + ((17-3*sqrt(17))/34)*(5-sqrt(17))^n [From Richard Choulet, Nov 20 2008]

CROSSREFS

Sequence in context: A156566 A055275 A155198 * A115970 A078995 A264913

Adjacent sequences:  A147837 A147838 A147839 * A147841 A147842 A147843

KEYWORD

nonn,easy

AUTHOR

Philippe Deléham, Nov 14 2008

STATUS

approved

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Last modified October 19 21:28 EDT 2019. Contains 328244 sequences. (Running on oeis4.)