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A172985 Triangle T(n,m) = A049614(n)/ (A049614(m)*A049614(n-m)) read by rows. 0
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 4, 4, 4, 1, 1, 1, 4, 4, 1, 1, 1, 6, 6, 24, 6, 6, 1, 1, 1, 6, 6, 6, 6, 1, 1, 1, 8, 8, 48, 12, 48, 8, 8, 1, 1, 9, 72, 72, 108, 108, 72, 72, 9, 1, 1, 10, 90, 720, 180, 1080, 180, 720, 90, 10, 1, 1, 1, 10, 90, 180, 180, 180, 180, 90, 10, 1, 1, 1, 12, 12, 120, 270 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,12

COMMENTS

Row sums are: 1, 2, 3, 4, 14, 12, 50, 28, 142, 524, 3082,...

LINKS

Table of n, a(n) for n=0..82.

EXAMPLE

1;

1, 1;

1, 1, 1;

1, 1, 1, 1;

1, 4, 4, 4, 1;

1, 1, 4, 4, 1, 1;

1, 6, 6, 24, 6, 6, 1;

1, 1, 6, 6, 6, 6, 1, 1;

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

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

1, 10, 90, 720, 180, 1080, 180, 720, 90, 10, 1;

MATHEMATICA

c[n_] := Product[If[i == 0, 1, If[PrimeQ[i], 1, i]], {i, 0, n}];

t[n_, m_] := c[n]/(c[m]*c[n - m]);

Table[Table[t[n, m], {m, 0, n}], {n, 0, 10}];

Flatten[%]

CROSSREFS

Sequence in context: A052283 A133889 A243756 * A117683 A172088 A159891

Adjacent sequences:  A172982 A172983 A172984 * A172986 A172987 A172988

KEYWORD

nonn,tabl,easy

AUTHOR

Roger L. Bagula, Feb 06 2010

EXTENSIONS

Definition simplified by the Assoc. Editors of the OEIS, Mar 05 2010

STATUS

approved

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Last modified June 5 15:20 EDT 2020. Contains 334850 sequences. (Running on oeis4.)