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A259348
a(n) = n^3 - 8.
0
-8, -7, 0, 19, 56, 117, 208, 335, 504, 721, 992, 1323, 1720, 2189, 2736, 3367, 4088, 4905, 5824, 6851, 7992, 9253, 10640, 12159, 13816, 15617, 17568, 19675, 21944, 24381, 26992, 29783, 32760, 35929, 39296, 42867, 46648, 50645, 54864, 59311, 63992
OFFSET
0,1
COMMENTS
The cubic number sequence whose geometrical arrangement loses all vertices: this is a figurate number represented by a cubic lattice of n^3 equispaced points without vertices.
FORMULA
G.f.: (-8 + 25*x - 20*x^2 + 9*x^3)/(1-x)^4. - Vincenzo Librandi, Jun 25 2015
a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4). - Vincenzo Librandi, Jun 25 2015
MATHEMATICA
Table[n^3 - 8, {n, 0, 40}] (* Vincenzo Librandi, Jun 25 2015 *)
LinearRecurrence[{4, -6, 4, -1}, {-8, -7, 0, 19}, 50] (* Harvey P. Dale, Sep 25 2017 *)
PROG
(Magma) [n^3 - 8: n in [0..40]]; // Vincenzo Librandi, Jun 25 2015
CROSSREFS
Sequence in context: A294969 A292821 A261303 * A257238 A348728 A255702
KEYWORD
sign,easy
AUTHOR
Luciano Ancora, Jun 24 2015
EXTENSIONS
First term -8 added from Vincenzo Librandi, Jun 25 2015
STATUS
approved