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A145335
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Numbers n such that there exists x in N : (x+1)^3-x^3=43*n^2.
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1
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7, 235963, 7954312723, 268139881656367, 9038995402681818847, 304704534756264231676003, 10271589857594671847116242283, 346255293794811853210024295683927, 11672265943551517714115247160388936887, 393472084610866368348013128566686766776843
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OFFSET
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1,1
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LINKS
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FORMULA
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a(n+2) = 33710*a(n+1)-a(n).
G.f.: -7*x*(x-1) / (x^2-33710*x+1). - Colin Barker, Oct 20 2014
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EXAMPLE
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a(1)=7 because the first relation is : 27^3-26^3=43*7^2.
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MATHEMATICA
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LinearRecurrence[{33710, -1}, {7, 235963}, 15] (* Paolo Xausa, Jan 17 2024 *)
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PROG
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(PARI) Vec(-7*x*(x-1)/(x^2-33710*x+1) + O(x^20)) \\ Colin Barker, Oct 20 2014
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CROSSREFS
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KEYWORD
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easy,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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