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A117683 Triangle T(n,m) read by rows: T(n,m) = A049614(n)/( A049614(m)*A049614(n-m) ) . 5
1, 1, 1, 1, 1, 1, 4, 4, 4, 1, 1, 4, 4, 1, 1, 6, 6, 24, 6, 6, 1, 1, 6, 6, 6, 6, 1, 1, 8, 8, 48, 12, 48, 8, 8, 1, 9, 72, 72, 108, 108, 72, 72, 9, 1, 10, 90, 720, 180, 1080, 180, 720, 90, 10, 1, 1, 10, 90, 180, 180, 180, 180, 90, 10, 1, 1, 12, 12, 120, 270, 2160, 360, 2160, 270, 120, 12, 12, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,7

LINKS

Table of n, a(n) for n=1..78.

EXAMPLE

1

1, 1

1, 1, 1

4, 4, 4, 1

1, 4, 4, 1, 1,

6, 6, 24, 6, 6, 1

1, 6, 6, 6, 6, 1, 1

8, 8, 48, 12, 48, 8, 8, 1

9, 72, 72, 108, 108, 72, 72, 9, 1

MATHEMATICA

cf[0] = 1; cf[n_Integer?Positive] := cf[n] = f[n]*cf[n - 1] bf[n_Integer?Positive, m_Integer?Positive] := bf[n, m] = cf[n]/(cf[m]*cf[n - m]) b = Table[Table[bf[n, m], {m, 1, n}], {n, 1, 10}] MatrixForm[b] Flatten[b]

PROG

(PARI) primorial(n)=prod(i=1, primepi(n), prime(i))

T(n, m)=binomial(n, m)*primorial(m)*primorial(n-m)/primorial(n) \\ Charles R Greathouse IV, Jan 16 2012

CROSSREFS

Sequence in context: A133889 A243756 A172985 * A172088 A159891 A201941

Adjacent sequences:  A117680 A117681 A117682 * A117684 A117685 A117686

KEYWORD

nonn,tabl

AUTHOR

Roger L. Bagula, Apr 12 2006

EXTENSIONS

Edited by the Associate Editors of the OEIS, Aug 18 2009

STATUS

approved

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Last modified January 16 15:21 EST 2021. Contains 340206 sequences. (Running on oeis4.)