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A123876
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Riordan array (1/(1+2x), x(1+x)/(1+2x)^2).
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3
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1, -2, 1, 4, -5, 1, -8, 18, -8, 1, 16, -56, 41, -11, 1, -32, 160, -170, 73, -14, 1, 64, -432, 620, -377, 114, -17, 1, -128, 1120, -2072, 1666, -704, 164, -20, 1, 256, -2816, 6496, -6608, 3649
(list; table; graph; refs; listen; history; internal format)
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OFFSET
| 0,2
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COMMENTS
| Inverse of A116395. Row sums are A123877. Diagonal sums are (-1)^n*A085810(n). Unsigned version is A114164.
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FORMULA
| Number triangle T(n,k)=(-1)^(n-k)*sum{j=0..n, C(k,j-k)*C(n,j)*2^(n-j)}
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EXAMPLE
| Triangle begins
1,
-2, 1,
4, -5, 1,
-8, 18, -8, 1,
16, -56, 41, -11, 1,
-32, 160, -170, 73, -14, 1
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CROSSREFS
| Sequence in context: A121574 A117317 A124237 * A114164 A176667 A126182
Adjacent sequences: A123873 A123874 A123875 * A123877 A123878 A123879
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KEYWORD
| easy,sign,tabl
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AUTHOR
| Paul Barry (pbarry(AT)wit.ie), Oct 16 2006
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