A296911 Partial sums of A296910.

1, 5, 11, 25, 39, 61, 83, 113, 143, 181, 219, 265, 311, 365, 419, 481, 543, 613, 683, 761, 839, 925, 1011, 1105, 1199, 1301, 1403, 1513, 1623, 1741, 1859, 1985, 2111, 2245, 2379, 2521, 2663, 2813, 2963, 3121, 3279, 3445, 3611, 3785, 3959, 4141, 4323, 4513, 4703, 4901, 5099, 5305, 5511, 5725

Offset

0,2

Links

Robert Israel, Table of n, a(n) for n = 0..10000

Reticular Chemistry Structure Resource (RCSR), The bew tiling (or net)

Index entries for linear recurrences with constant coefficients, signature (2,0,-2,1).

Formula

From Robert Israel, Dec 22 2017: (Start)

a(n) = 2*n^2 + 2*n - (-1)^n for n >= 1.

G.f.: (1+3*x+x^2+5*x^3-2*x^4)/((1+x)*(1-x)^3). (End)

a(n) ~ 2*n^2. - Charles R Greathouse IV, May 31 2026

Maple

1, seq(2*n^2 + 2*n - (-1)^n, n=1..100); # Robert Israel, Dec 22 2017

Mathematica

LinearRecurrence[{2, 0, -2, 1}, {1, 5, 11, 25, 39}, 60] (* Paolo Xausa, Jun 07 2026 *)

Prog

(PARI) a(n)=if(n, 2*n^2+2*n-(-1)^n, 1) \\ Charles R Greathouse IV, May 31 2026

Crossrefs

Cf. A296910.

Sequence in context: A021008 A266905 A059358 * A381710 A167238 A376763

Adjacent sequences: A296908 A296909 A296910 * A296912 A296913 A296914

Keyword

nonn,easy,changed

Author

N. J. A. Sloane, Dec 22 2017

Status

approved