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A081583
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Third row of Pascal-(1,2,1) array A081577.
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2
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1, 10, 46, 136, 307, 586, 1000, 1576, 2341, 3322, 4546, 6040, 7831, 9946, 12412, 15256, 18505, 22186, 26326, 30952, 36091, 41770, 48016, 54856, 62317, 70426, 79210, 88696, 98911, 109882, 121636, 134200, 147601, 161866, 177022, 193096
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,2
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COMMENTS
| Equals binomial transform of [1, 9, 27, 27, 0, 0, 0,...] where (1, 9, 27, 27) = row 3 of triangle A013610. - Gary W. Adamson (qntmpkt(AT)yahoo.com), Jul 19 2008
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FORMULA
| a(n)=(2+9n+9n^3)/2. G.f. (1+2x)^3/(1-x)^4.
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CROSSREFS
| Cf. A038764, A081584.
Cf. A013610.
Sequence in context: A007941 A007940 A082604 * A106600 A085437 A024166
Adjacent sequences: A081580 A081581 A081582 * A081584 A081585 A081586
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KEYWORD
| easy,nonn
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AUTHOR
| Paul Barry (pbarry(AT)wit.ie), Mar 23 2003
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