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A121574
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Riordan array (1/(1-2x), x(1+x)/(1-2x)).
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1
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1, 2, 1, 4, 5, 1, 8, 16, 8, 1, 16, 44, 37, 11, 1, 32, 112, 134, 67, 14, 1, 64, 272, 424, 305, 106, 17, 1, 128, 640, 1232, 1168, 584, 154, 20, 1, 256, 1472, 3376, 3992, 2641, 998, 211, 23, 1, 512, 3328, 8864, 12592, 10442, 5221, 1574, 277, 26, 1, 1024, 7424, 22528
(list; table; graph; refs; listen; history; internal format)
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OFFSET
| 0,2
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COMMENTS
| Row sums are A006190(n+1); diagonal sums are A077939. Inverse is A121575. A generalized Delannoy number triangle.
Antidiagonal sums are A002478. - From DELEHAM Philippe, Nov 10 2011.
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FORMULA
| Number array T(n,k)=sum{j=0..n-k, C(k,j)C(n-j,k)2^(n-k-j)}
T(n,k) = 2*T(n-1,k) + T(n-1,k-1) + T(n-2,k-1). - From DELEHAM Philippe, Nov 10 2011
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EXAMPLE
| Triangle begins
1
2, 1
4, 5, 1
8, 16, 8, 1
16, 44, 37, 11, 1
32, 112, 134, 67, 14, 1
64, 272, 424, 305, 106, 17, 1
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CROSSREFS
| Cf. Diagonals : A000012, A016789, A080855, A000079, A053220.
Sequence in context: A134248 A080935 A102661 * A117317 A124237 A123876
Adjacent sequences: A121571 A121572 A121573 * A121575 A121576 A121577
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KEYWORD
| easy,nonn,tabl
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AUTHOR
| Paul Barry (pbarry(AT)wit.ie), Aug 08 2006
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