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A145306
Numbers n such that there exists x in N : (x+79)^3-x^3=n^2.
1
118579, 54107716279, 24689459153421679, 11265849590570511254779, 5140629699851815967424745579, 2345679613290517479977275745934079, 1070338298898549077448739061453787370279, 488397506461660061524724013739508808887114179
OFFSET
1,1
FORMULA
a(n+2) = 456302*a(n+1)-a(n);
G.f. -118579*x*(-1+x) / ( 1-456302*x+x^2 ). - R. J. Mathar, Nov 27 2011
EXAMPLE
a(1)=118579 because the first relation is (7663+79)^3-7663^3=118579^2.
MATHEMATICA
LinearRecurrence[{456302, -1}, {118579, 54107716279}, 10] (* Paolo Xausa, Jan 17 2024 *)
PROG
(PARI) Vec(-118579*x*(-1+x)/(1-456302*x+x^2) + O(x^30)) \\ Colin Barker, Oct 18 2014
CROSSREFS
Cf. A145307.
Sequence in context: A235837 A235832 A111112 * A250370 A202285 A250829
KEYWORD
easy,nonn
AUTHOR
Richard Choulet, Oct 06 2008
EXTENSIONS
Editing and more terms from Colin Barker, Oct 18 2014
STATUS
approved