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A145212
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Numbers x such that there exists n in N : (x+1)^3 - x^3 = 67*n^2.
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3
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146, 150922981, 155479346311338, 160173267776326886333, 165008898730338715685597026, 169990517382847468244368873843701, 175122531102470624411936031429357251258, 180409480316284222045549532749965177800150413
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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) = 1030190*a(n+1)-a(n)+515094.
G.f.: x*(146+515095*x-147*x^2) / ((1-x)*(1-1030190*x+x^2)). - Colin Barker, Oct 18 2014, corrected Jul 13 2016
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EXAMPLE
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The first relation is : 147^3-146^3=67*31^2.
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PROG
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(PARI) Vec(x*(146+515095*x-147*x^2)/((1-x)*(1-1030190*x+x^2)) + O(x^10)) \\ Colin Barker, Oct 18 2014, corrected Jul 13 2016
(PARI) isok(x) = issquare(((x+1)^3-x^3)/67) \\ Colin Barker, Jul 13 2016
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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EXTENSIONS
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Editing and additional term a(8) from Colin Barker, Oct 18 2014
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STATUS
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approved
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