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A144155 Bell convolution triangle, T(n,k) = A000110(n-k)*A000110(k) 1
1, 1, 1, 2, 1, 2, 5, 2, 2, 5, 15, 5, 4, 5, 15, 52, 15, 10, 10, 15, 52, 203, 52, 30, 25, 30, 52, 203, 877, 203, 104, 75, 75, 104, 203, 877, 4140, 877, 406, 260, 225, 260, 406, 877, 4140, 21147, 4140, 1754, 1015, 780, 780, 1015, 1754, 4140, 21147 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,4

COMMENTS

Row sums = A014322: (1, 2, 5, 14, 44, 154,...) the Bell numbers convolved with themselves.

LINKS

Table of n, a(n) for n=0..54.

FORMULA

Triangle read by rows, T(n,k) = A000110(n-k)*A000110(k)

EXAMPLE

First few rows of the triangle =

1;

1, 1;

2, 1, 2;

5, 2, 2, 5;

15, 5, 4, 5, 15;

52, 15, 10, 10, 15, 52;

203, 52, 30, 25, 30, 52, 203;

...

Row 3 = (5, 2, 2, 5) = termwise products of (1, 1, 2, 5) and (5, 2, 1, 1) = (5*1, 1*2, 2*1, 5*1).

CROSSREFS

A000110, Cf. A014322

Sequence in context: A147292 A078391 A153206 * A109631 A337222 A095149

Adjacent sequences:  A144152 A144153 A144154 * A144156 A144157 A144158

KEYWORD

nonn,tabl

AUTHOR

Gary W. Adamson, Sep 12 2008

EXTENSIONS

More terms from Philippe Deléham, Jan 29 2012

STATUS

approved

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Last modified April 15 02:27 EDT 2021. Contains 342974 sequences. (Running on oeis4.)