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A156732 A triangular sequence: t(n,m)=((n + 1 - 2*m)^2/(n + 1 - m))*Binomial[n, m]. +0
1
0, 1, 1, 4, 0, 4, 9, 2, 2, 9, 16, 10, 0, 10, 16, 25, 27, 5, 5, 27, 25, 36, 56, 28, 0, 28, 56, 36, 49, 100, 84, 14, 14, 84, 100, 49, 64, 162, 192, 84, 0, 84, 192, 162, 64, 81, 245, 375, 270, 42, 42, 270, 375, 245, 81 (list; table; graph; listen)
OFFSET

0,4

COMMENT

Row sums are:

{0, 2, 10, 36, 108, 290, 726, 1736, 4024, 9126, 20370,...}.

From the Riordan Identity:

2^n=Table[Sum[(( n + 1 - 2*m)^2/(n + 1 - m))*Binomial[n, m], {m, 0, Floor[n/2]}], {n, 0, 10}].

Because of the central zeros,

I call it an hollow sequence.

REFERENCES

J. Riordan, Combinatorial Identities, Wiley, 1968

FORMULA

t(n,m)=((n + 1 - 2*m)^2/(n + 1 - m))*Binomial[n, m].

EXAMPLE

{0},

{1, 1},

{4, 0, 4},

{9, 2, 2, 9},

{16, 10, 0, 10, 16},

{25, 27, 5, 5, 27, 25},

{36, 56, 28, 0, 28, 56, 36},

{49, 100, 84, 14, 14, 84, 100, 49},

{64, 162, 192, 84, 0, 84, 192, 162, 64},

{81, 245, 375, 270, 42, 42, 270, 375, 245, 81}

MATHEMATICA

Table[Table[((n + 1 - 2* m)^2/(n + 1 - m))*Binomial[n, m], {m, 1, n}], {n, 1, 10}];

Flatten[%]

CROSSREFS

Sequence in context: A055951 A165032 A088374 this_sequence A101980 A058536 A154854

Adjacent sequences: A156729 A156730 A156731 this_sequence A156733 A156734 A156735

KEYWORD

nonn,tabl,uned

AUTHOR

Roger L. Bagula (rlbagulatftn(AT)yahoo.com), Feb 14 2009

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Last modified December 2 11:54 EST 2009. Contains 167921 sequences.


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