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A108983 Inverse binomial transform of A003950. 0
1, 7, 41, 247, 1481, 8887, 53321, 319927, 1919561, 11517367, 69104201, 414625207, 2487751241, 14926507447, 89559044681, 537354268087, 3224125608521, 19344753651127, 116068521906761, 696411131440567, 4178466788643401 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

COMMENTS

Let A be the Hessenberg matrix of order n, defined by: A[1,j]=1, A[i,i]:=-4, (i>1), A[i,i-1]=-1, and A[i,j]=0 otherwise. Then, for n>=1, a(n-1)=charpoly(A,2). [From Milan R. Janjic (agnus(AT)blic.net), Jan 27 2010]

FORMULA

a(n) = 5a(n-1) + 6a(n-2), a(0) = 1, a(1) = 7.

a(2n) = 6a(2n-1) - 1; a(2n+1) = 6a(2n) + 1.

O.g.f.: -(1+2x)/[(1+x)(6x-1)]. - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Apr 02 2008

a(n)=-(1/7)*[(-1)^n-8*6^n], with n>=0 [From Paolo P. Lava (paoloplava(AT)gmail.com), Nov 19 2008]

CROSSREFS

Sequence in context: A002315 A141813 A088165 * A115137 A036730 A080047

Adjacent sequences:  A108980 A108981 A108982 * A108984 A108985 A108986

KEYWORD

nonn

AUTHOR

Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Jul 23 2005

EXTENSIONS

More terms from R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Apr 02 2008

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Last modified February 16 09:27 EST 2012. Contains 205904 sequences.