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A145212
Numbers x such that there exists n in N : (x+1)^3 - x^3 = 67*n^2.
3
146, 150922981, 155479346311338, 160173267776326886333, 165008898730338715685597026, 169990517382847468244368873843701, 175122531102470624411936031429357251258, 180409480316284222045549532749965177800150413
OFFSET
1,1
FORMULA
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
EXAMPLE
The first relation is : 147^3-146^3=67*31^2.
PROG
(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
CROSSREFS
Sequence in context: A172877 A172911 A172933 * A195239 A122064 A320511
KEYWORD
nonn,easy
AUTHOR
Richard Choulet, Oct 04 2008
EXTENSIONS
Editing and additional term a(8) from Colin Barker, Oct 18 2014
a(2) to a(8) corrected by Colin Barker, Jul 13 2016
STATUS
approved