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A120624
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Numbers n such that the n-th Catalan number C(2n,n)/(n+1) is divisible by 2n.
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1
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6, 28, 42, 45, 66, 77, 91, 110, 126, 140, 153, 156, 170, 187, 190, 204, 209, 210, 220, 228, 231, 238, 266, 276, 299, 308, 312, 315, 322, 325, 330, 345, 378, 414, 420, 429, 435, 440, 442, 450, 459, 460, 468, 476, 483, 493, 496, 510, 527, 551, 558, 561, 570
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| Equivalently, numbers such that the n-th central binomial coefficient C(2n, n) is divisible by 2n(n + 1). - Joel B. Lewis (jblewis(AT)post.harvard.edu), Jan 07 2008
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MATHEMATICA
| fQ[n_] := fQ[n_] := IntegerQ[ Binomial[2n, n]/(2n(n + 1))]; Select[ Range@8719, fQ@# &]
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CROSSREFS
| Subset of A104847. Cf. A120622.
Sequence in context: A117948 A071834 A055196 * A138873 A091307 A058007
Adjacent sequences: A120621 A120622 A120623 * A120625 A120626 A120627
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KEYWORD
| nonn
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AUTHOR
| Robert G. Wilson v (rgwv(AT)rgwv.com), Jun 19 2006
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EXTENSIONS
| Definition corrected by Joel Brewster Lewis (jblewis(AT)post.harvard.edu), Apr 30 2009
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