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A117684 Sum of the rows of Compositnomial function: a triangular binomial like function made up of a product of only composite numbers. +0
1
1, 2, 3, 13, 11, 49, 27, 141, 523, 3081, 923, 5509, 1371, 7617, 24391, 84933, 14795, 110329, 20859, 142101, 499843, 1858209, 241211, 2312077, 8417451 (list; graph; listen)
OFFSET

0,2

COMMENT

In contrast to Pascal's triangle these sums alternate in Magnitude.

FORMULA

f[n]= 1 if n is prime and n otherwise cf[0]=1; cf(n) = f[n]*a[n-1] bf[n,m]=cf[n]/(cf[m]*cf[n - m]) a[n]=Sum[bf[n,m],{m,1,n}]

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] c = Table[Apply[Plus, Table[bf[n, m], {m, 1, n}]], {n, 1, 25}] ListPlot[c, PlotJoined -> True]

CROSSREFS

Sequence in context: A074478 A132365 A129671 this_sequence A056445 A100385 A128460

Adjacent sequences: A117681 A117682 A117683 this_sequence A117685 A117686 A117687

KEYWORD

nonn,uned,probation

AUTHOR

Roger L. Bagula (rlbagulatftn(AT)yahoo.com), Apr 12 2006

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Last modified November 18 20:14 EST 2008. Contains 147244 sequences.


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