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A108080
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Sum [i=0..n, C(2n+i,n-i) ].
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1
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1, 3, 12, 50, 211, 895, 3805, 16193, 68940, 293526, 1249622, 5318976, 22634700, 96296410, 409573584, 1741574006, 7403616923, 31466106703, 133704121665, 568008916093, 2412570019447, 10245302874071, 43500597657111
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,2
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COMMENTS
| Row sums of A159965. [From Paul Barry (pbarry(AT)wit.ie), Apr 28 2009]
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FORMULA
| Contribution from Paul Barry (pbarry(AT)wit.ie), Apr 28 2009: (Start)
G.f.: x/(x*sqrt(1-4x)-(1-2x-(1-3x)*c(x))), c(x) the g.f. of A000108.
a(n)=sum{k=0..n, sum{j=0..n, C(n+k,j-k)*C(n,j)}}. (End)
Contribution from Paul Barry (pbarry(AT)wit.ie), Sep 07 2009: (Start)
G.f.: (1/sqrt(1-4x))*(1/(1-xc(x)^3)), c(x) the g.f. of A000108;
a(n):=sum{k=0..n, C(2n,n-k)*F(k+1)}=sum{k=0..n, C(2n,k)*F(n-k+1)};
a(n):=sum{k=0..n, C(2k,k)* A165201(n-k)}. (End)
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CROSSREFS
| Apparently a bisection of A026847.
Sequence in context: A037765 A037653 A092443 * A113441 A119976 A074547
Adjacent sequences: A108077 A108078 A108079 * A108081 A108082 A108083
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KEYWORD
| nonn
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AUTHOR
| Ralf Stephan, Jun 03 2005
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