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A117399

Column 1 (divided by 2) of triangle A117398, which is the matrix log of A117396.

1, 1, 2, 7, 34, 202, 1402, 11122, 99322, 986362, 10784122, 128720122, 1665516922, 23220588922, 347025670522, 5534133996922, 93802153836922, 1683934185324922, 31917365573484922, 636941680764780922, 13348854673487724922

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OFFSET

1,3

LINKS

G. C. Greubel, Table of n, a(n) for n = 1..250

MATHEMATICA

m=42;

M= Table[If[k>n-1, 0, If[k==n-1, n, -1]], {n, 0, m+1}, {k, 0, m+1}];

T:= T= Sum[MatrixPower[M, j]/j, {j, m+1}];

Table[T[[n+1, 2]]/2, {n, 2, 30}] (* G. C. Greubel, Sep 06 2022 *)

PROG

(PARI) {a(n)=local(M=matrix(n+4, n+4, r, c, if(r>=c, if(r==c+1, -c, 1))), L=sum(m=1, n+4, (M^0-M)^m/m)); L[n+2, 2]/2}

CROSSREFS

Cf. A117398, A117396.

Sequence in context: A393920 A307696 A237645 * A145345 A212027 A056543

Adjacent sequences: A117396 A117397 A117398 * A117400 A117401 A117402

KEYWORD

nonn

AUTHOR

Paul D. Hanna, Mar 11 2006

STATUS

approved

URL: https://oeis.org/A117399

⇱ A117399 - OEIS