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A117352 Riordan array (1/(1-2x), x(1-2x)/(1-x)). 2
1, 2, 1, 4, 1, 1, 8, 1, 0, 1, 16, 1, -1, -1, 1, 32, 1, -2, -2, -2, 1, 64, 1, -3, -2, -2, -3, 1, 128, 1, -4, -1, 0, -1, -4, 1, 256, 1, -5, 1, 3, 3, 1, -5, 1, 512, 1, -6, 4, 6, 6, 6, 4, -6, 1, 1024, 1, -7, 8, 8, 6, 6, 8, 8, -7, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET
0,2
COMMENTS
Row sums are A038505. Diagonal sums are A117353. Inverse is A117354.
LINKS
FORMULA
Number triangle T(n,k)=sum{j=0..n-k, C(j-k,j)C(n-k,j)}
EXAMPLE
Triangle begins
1,
2, 1,
4, 1, 1,
8, 1, 0, 1,
16, 1, -1, -1, 1,
32, 1, -2, -2, -2, 1,
64, 1, -3, -2, -2, -3, 1
CROSSREFS
Sequence in context: A238415 A283826 A088443 * A137710 A068009 A140168
KEYWORD
easy,sign,tabl
AUTHOR
Paul Barry, Mar 09 2006
STATUS
approved

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Last modified March 29 11:14 EDT 2024. Contains 371278 sequences. (Running on oeis4.)