A258130 Octagonal numbers (A000567) that are the sum of ten consecutive octagonal numbers.

1045, 1325345, 1910970885, 2755618515265, 3973599987865685, 5729928426883626945, 8262552817966202013445, 11914595433578836419585185, 17180838352667864150839647765, 24774756989951626526674352316385, 35725182398671892783600265200403845

Offset

1,1

Links

Colin Barker, Table of n, a(n) for n = 1..316

Index entries for linear recurrences with constant coefficients, signature (1443,-1443,1).

Formula

G.f.: -95*x*(63*x^2 - 1922*x + 11)/((x - 1)*(x^2 - 1442*x + 1)).

Example

1045 is in the sequence because Oct(19) = 1045 = 1+8+21+40+65+96+133+176+225+280 = Oct(1) + ... + Oct(10).

Mathematica

CoefficientList[Series[-95 x (63 x^2 - 1922 x + 11)/((x - 1) (x^2 - 1442 x + 1)), {x, 0, 50}], x] (* G. C. Greubel, Oct 18 2017 *)
LinearRecurrence[{1443, -1443, 1}, {1045, 1325345, 1910970885}, 20] (* Harvey P. Dale, Jul 25 2019 *)

Prog

(PARI) Vec(-95*x*(63*x^2-1922*x+11)/((x-1)*(x^2-1442*x+1)) + O('x^20))

Crossrefs

Cf. A000567, A258128, A258129, A258131, A258132.

Sequence in context: A023067 A344410 A110597 * A226114 A249653 A056092

Adjacent sequences: A258127 A258128 A258129 * A258131 A258132 A258133

Keyword

nonn,easy

Author

Colin Barker, May 21 2015

Status

approved