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A087347
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Numbers k that divide Sum_{j=1..k} Fibonacci(j*k).
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1
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1, 2, 5, 8, 12, 15, 20, 24, 25, 32, 36, 44, 48, 50, 56, 60, 63, 72, 80, 84, 95, 96, 104, 108, 110, 120, 125, 128, 135, 140, 144, 152, 155, 168, 175, 180, 185, 192, 200, 204, 207, 209, 216, 224, 228, 240, 252, 264, 276, 279, 288, 300, 320, 323, 324, 336, 360, 368
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OFFSET
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1,2
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LINKS
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FORMULA
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Conjecture: a(n) is asymptotic to c*n*log(n) with c around 1.3. [This conjecture is probably false, see plot. - Vaclav Kotesovec, Feb 16 2019]
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MATHEMATICA
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Select[Range[380], Divisible[Sum[Fibonacci[# k], {k, #}], #]&] (* Harvey P. Dale, Aug 16 2011 *)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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