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Search: id:A071255
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| A071255 |
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a(1) = 2, a(n+1) = a(n)-th squarefree number. |
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+0
4
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| 2, 3, 5, 7, 11, 17, 29, 46, 74, 119, 195, 319, 521, 859, 1407, 2315, 3810, 6267, 10303, 16942, 27862, 45822, 75381, 123998, 203969, 335507
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OFFSET
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1,1
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COMMENT
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Here 1 is not considered a squarefree number.
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EXAMPLE
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a(2) = 3 and the third squarefree number is 5 hence a(3) = 5.
a(4) = 7 hence a(5) = 11 is the 7-th squarefree number (2,3,5,6,7,10,11...)
75381 is the 45822-nd squarefree number.
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MATHEMATICA
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Needs["NumberTheory`NumberTheoryFunctions`"]; sqf = {}; Do[ If[ SquareFreeQ[n], sqf = Append[sqf, n]], {n, 2, 334000} ]; a[1] = 2; a[n_] := sqf[[ a[n - 1]]]; Table[ a[n], {n, 1, 26}].
a[1]=2; a[x_] := Part[t, a[x-1]] t=Flatten[Position[Table[Abs[MoebiusMu[w]], {w, 2, 35000}], 1]]+1; t1=Table[a[w], {w, 1, 21}]
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CROSSREFS
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a(n)=A005117[a(n-1)], a(1)=2
Sequence in context: A127272 A113192 A077673 this_sequence A062294 A113016 A085136
Adjacent sequences: A071252 A071253 A071254 this_sequence A071256 A071257 A071258
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KEYWORD
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nonn
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AUTHOR
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Amarnath Murthy (amarnath_murthy(AT)yahoo.com), May 22 2002
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EXTENSIONS
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More terms from Robert G. Wilson v (rgwv(AT)rgwv.com) and Labos E. (labos(AT)ana.sote.hu), Jun 07 2002
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