A084382 a(n) = n^3 + 6.

6, 7, 14, 33, 70, 131, 222, 349, 518, 735, 1006, 1337, 1734, 2203, 2750, 3381, 4102, 4919, 5838, 6865, 8006, 9267, 10654, 12173, 13830, 15631, 17582, 19689, 21958, 24395, 27006, 29797, 32774, 35943, 39310, 42881, 46662, 50659, 54878, 59325, 64006

Offset

0,1

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..1000

Cino Hilliard, Proof that a cube plus 7 cannot be a square

Index entries for linear recurrences with constant coefficients, signature (4,-6,4,-1).

Formula

a(1)=7, a(2)=14, a(3)=33, a(4)=70; for n>4, a(n) = 4*a(n-1)-6*a(n-2)+4*a(n-3)-a(n-4). - Harvey P. Dale, Aug 08 2013

G.f.: (6 - 17*x + 22*x^2 - 5*x^3)/(1 - x)^4. - Vincenzo Librandi, Jun 10 2016

Mathematica

Table[n^3 + 6, {n, 0, 60}] (* Vladimir Joseph Stephan Orlovsky, Apr 15 2011 *)
LinearRecurrence[{4, -6, 4, -1}, {6, 7, 14, 33}, 60] (* Harvey P. Dale, Aug 08 2013 *)

Prog

(PARI) a(n) = n^3 + 6;
(Magma) [n^3+6: n in [0..50]]; // Vincenzo Librandi, Jun 10 2016

Crossrefs

Cf. A000578, A084378, A084381.

Sequence in context: A022311 A219382 A047915 * A315842 A085512 A165767

Adjacent sequences: A084379 A084380 A084381 * A084383 A084384 A084385

Keyword

nonn,easy

Author

Cino Hilliard, Jun 23 2003

Extensions

Offset 0 and a(0) = 6 from Vincenzo Librandi, Jun 10 2016

Status

approved