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A124861
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Expansion of 1/(1-x-3x^2-4x^3-2x^4).
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1
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1, 1, 4, 11, 29, 80, 219, 597, 1632, 4459, 12181, 33280, 90923, 248405, 678656, 1854123, 5065557, 13839360, 37809835, 103298389, 282216448, 771029675, 2106492245, 5755043840, 15723072171, 42956232021, 117358608384
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,3
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COMMENTS
| Diagonal sums of number triangle A124860.
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FORMULA
| a(n)=a(n-1)+3a(n-2)+4a(n-3)+2a(n-4); a(n)=sum{k=0..floor(n/2), J(n-k+1)C(n-k,k)} where J(n)=A001045(n). - corrected by Harvey P. Dale, Apr 22 2011
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MATHEMATICA
| LinearRecurrence[{1, 3, 4, 2}, {1, 1, 4, 11}, 30] (* or *) CoefficientList[ Series[ 1/(1-x-3x^2-4x^3-2x^4), {x, 0, 30}], x] (* From Harvey P. Dale, Apr 22 2011 *)
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CROSSREFS
| Sequence in context: A027972 A098149 A002878 * A110579 A084378 A099065
Adjacent sequences: A124858 A124859 A124860 * A124862 A124863 A124864
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KEYWORD
| easy,nonn
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AUTHOR
| Paul Barry (pbarry(AT)wit.ie), Nov 10 2006
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