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A141604 Triangle t(n,m)= round( A006720(n)/(A006720(n-m)*A006720(m)) read by rows, 0<=m<=n. 1
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 1, 1, 2, 3, 3, 2, 1, 1, 2, 4, 7, 4, 2, 1, 1, 3, 8, 12, 12, 8, 3, 1, 1, 3, 8, 20, 15, 20, 8, 3, 1, 1, 5, 14, 45, 52, 52, 45, 14, 5, 1, 1, 5, 26, 66, 109, 170, 109, 66, 26, 5, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,12

COMMENTS

The round-function in the definition is round-to-nearest, not Mathematica's round-to-even. - R. J. Mathar, Jul 12 2012

Row sums are 1, 2, 3, 4, 8, 12, 21, 48, 79, 234, 584..

LINKS

Table of n, a(n) for n=0..65.

EXAMPLE

1;

1, 1;

1, 1, 1;

1, 1, 1, 1;

1, 2, 2, 2, 1;

1, 2, 3, 3, 2, 1;

1, 2, 4, 7, 4, 2, 1;

1, 3, 8, 12, 12, 8, 3, 1;

1, 3, 8, 20, 15, 20, 8, 3, 1;

1, 5, 14, 45, 52, 52, 45, 14, 5, 1;

1, 5, 26, 66, 109, 170, 109, 66, 26, 5, 1;

MAPLE

A141604 := proc(n, m)

        round(A006720(n)/A006720(n-m)/A006720(m)) ;

end proc:

seq(seq(A141604(n, k), k=0..n), n=0..12) ; # R. J. Mathar, Jul 12 2012

MATHEMATICA

Clear[a, t] (*A006720*) (* _Robert G.Wilson v_, Jul 04 2007 *) a[0] = a[1] = a[2] = a[3] = 1; a[n_] := a[n] = (a[n - 1] a[n - 3] + a[n - 2]^2)/a[n - 4]; Array[a, 23]; t[n_, m_] := a[n]/(a[n - m]*a[m]) Table[Table[Round[t[n, m]], {m, 0, n}], {n, 0, 10}]; Flatten[%]

CROSSREFS

Cf. A006720.

Sequence in context: A134143 A295555 A085684 * A143996 A301562 A334486

Adjacent sequences:  A141601 A141602 A141603 * A141605 A141606 A141607

KEYWORD

nonn,less,tabl

AUTHOR

Roger L. Bagula and Gary W. Adamson, Aug 21 2008

STATUS

approved

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Last modified June 1 19:32 EDT 2020. Contains 334762 sequences. (Running on oeis4.)