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A112743 An aerated Delannoy triangle. 0
1, 0, 1, 1, 0, 1, 0, 3, 0, 1, 1, 0, 5, 0, 1, 0, 5, 0, 7, 0, 1, 1, 0, 13, 0, 9, 0, 1, 0, 7, 0, 25, 0, 11, 0, 1, 1, 0, 25, 0, 41, 0, 13, 0, 1, 0, 9, 0, 63, 0, 61, 0, 15, 0, 1, 1, 0, 41, 0, 129, 0, 85, 0, 17, 0, 1, 0, 11, 0, 129, 0, 231, 0, 113, 0, 19, 0, 1, 1, 0, 61, 0, 321, 0, 377, 0, 145, 0, 21, 0, 1 (list; table; graph; refs; listen; history; internal format)
OFFSET

0,8

COMMENTS

Row sums are Tribonacci numbers A000073. Diagonal sums are aerated Pell numbers.

FORMULA

Riordan array (1/(1-x^2), x(1+x^2)/(1-x^2)); Number triangle T(n, k)=if(k<=n, sum{j=0..k, (1+(-1)^(n-k))C(k, j)C((n-k)/2, j)2^j/2}, 0).

EXAMPLE

Rows begin

1;

0,1;

1,0,1;

0,3,0,1;

1,0,5,0,1;

0,5,0,7,0,1;

1,0,13,0,9,0,1;

0,7,0,25,0,11,0,1;

1,0,25,0,41,0,13,0,1;

CROSSREFS

Cf. A008288.

Sequence in context: A188832 A094675 A200472 * A119467 A166353 A110235

Adjacent sequences:  A112740 A112741 A112742 * A112744 A112745 A112746

KEYWORD

easy,nonn,tabl

AUTHOR

Paul Barry (pbarry(AT)wit.ie), Sep 17 2005

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Last modified February 16 20:01 EST 2012. Contains 205955 sequences.