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A103778
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Inverse of trinomial triangle A071675.
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1
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1, 0, 1, 0, -1, 1, 0, 1, -2, 1, 0, 0, 3, -3, 1, 0, -4, -2, 6, -4, 1, 0, 14, -7, -7, 10, -5, 1, 0, -30, 36, -6, -16, 15, -6, 1, 0, 33, -96, 63, 3, -30, 21, -7, 1, 0, 55, 154, -209, 88, 25, -50, 28, -8, 1, 0, -429, 0, 429, -374, 99, 66, -77, 36, -9, 1, 0, 1365, -1014
(list; table; graph; refs; listen; history; internal format)
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OFFSET
| 0,9
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COMMENTS
| Inverse of Riordan array (1, x(1+x+x^2)) (A071675).
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FORMULA
| Riordan array (1, y) where y satisfies y+y^2+y^3=x; y=-2^(2/3)((3sqrt(3)sqrt(27x^2+14x+3)-27x-7)^(1/3)-(3sqrt(3)sqrt(27x^2+14x+3)+27x+7)^(1/3) +2^(1/3))/6.
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EXAMPLE
| Rows start {1}, {0,1}, {0,-1,1}, {0,1,-2,1}, {0,0,3,-3,1},...
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CROSSREFS
| Sequence in context: A106237 A071675 A034365 * A099423 A071920 A065719
Adjacent sequences: A103775 A103776 A103777 * A103779 A103780 A103781
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KEYWORD
| easy,sign,tabl
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AUTHOR
| Paul Barry (pbarry(AT)wit.ie), Feb 15 2005
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