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A122919
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Inverse of Riordan array (1/(1+x+x^2),x/(1+x)^2).
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2
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1, 1, 1, 3, 3, 1, 9, 10, 5, 1, 28, 34, 21, 7, 1, 90, 117, 83, 36, 9, 1, 297, 407, 319, 164, 55, 11, 1, 1001, 1430, 1209, 702, 285, 78, 13, 1, 3432, 5070, 4550, 2898, 1350, 454, 105, 15, 1, 11934, 18122, 17068, 11696, 6052
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OFFSET
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0,4
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COMMENTS
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LINKS
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FORMULA
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Riordan array ((1-3x+2x^2-(1-x)sqrt(1-4x))/(2x^2),(1-2x-sqrt(1-4x))/(2x))
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EXAMPLE
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Triangle begins
1,
1, 1,
3, 3, 1,
9, 10, 5, 1,
28, 34, 21, 7, 1,
90, 117, 83, 36, 9, 1,
297, 407, 319, 164, 55, 11, 1,
1001, 1430, 1209, 702, 285, 78, 13, 1
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CROSSREFS
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KEYWORD
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AUTHOR
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STATUS
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approved
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