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A119901
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Difference between two consecutive squares enclosing 3^(2n+1).
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0
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3, 11, 31, 93, 281, 841, 2525, 7575, 22727, 68183, 204551, 613655, 1840965, 5522897, 16568691, 49706071, 149118215, 447354647, 1342063941, 4026191825, 12078575475, 36235726425, 108707179277, 326121537829, 978364613487
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,1
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FORMULA
| a(n) = 2*Floor(3^((2n + 1)/2)) + 1.
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EXAMPLE
| a(2)=31 because 3^(2*2+1)=3^5=243, 15^2<243<16^2 and 16^2-15^2=256-225=31
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MATHEMATICA
| f[n_] := 2*Floor[3^((2n + 1)/2)] + 1; Table[f[n], {n, 0, 25}] (*Chandler*)
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CROSSREFS
| Sequence in context: A034543 A054343 A108898 * A106934 A146581 A146456
Adjacent sequences: A119898 A119899 A119900 * A119902 A119903 A119904
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KEYWORD
| nonn
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AUTHOR
| Zak Seidov (zakseidov(AT)yahoo.com), May 27 2006
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EXTENSIONS
| Extended by Ray Chandler (rayjchandler(AT)sbcglobal.net), Jun 09 2006
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