A123236 a(n) = 10*a(n-1) + 44*a(n-2) - 370*a(n-3) - 240*a(n-4) + 2400*a(n-5), a(1) = 1, a(2) = 1, a(3) = 31, a(4) = 134, a(5) = 2094, for n >= 6.

1, 1, 31, 134, 2094, 17526, 212776, 2166364, 24360204, 261014296, 2871433416, 31176422744, 340884832864, 3714001624016, 40540962761456, 442107409651424, 4823706911830624, 52616402130339936, 574011156687808896, 6261654235546867904, 68308332585830561984

Offset

1,3

Links

G. C. Greubel, Table of n, a(n) for n = 1..962

Index entries for linear recurrences with constant coefficients, signature (10,44,-370,-240,2400).

Formula

G.f.: x*(1-9*x-23*x^2+150*x^3) / (1 - 2*x*(5+22*x-185*x^2-120*x^3+1200*x^4)). - Elmo R. Oliveira, May 11 2026

Maple

a[1]:=1: a[2]:=1: a[3]:=31: a[4]:=134: a[5]:=2094: for n from 6 to 20 do a[n]:=10*a[n-1]+44*a[n-2]-370*a[n-3]-240*a[n-4]+2400*a[n-5] od: seq(a[n], n=1..20);

Mathematica

LinearRecurrence[{10, 44, -370, -240, 2400}, {1, 1, 31, 134, 2094}, 50] (* G. C. Greubel, Oct 12 2018 *)

Prog

(PARI) m=50; v=concat([1, 1, 31, 134, 2094], vector(m-5)); for(n=6, m, v[n] = 10*v[n-1] +44*v[n-2] -370*v[n-3] -240*v[n-4] + 2400*v[n-5]); v \\ G. C. Greubel, Oct 12 2018
(Magma) I:=[1, 1, 31, 134, 2094]; [n le 5 select I[n] else 10*Self(n-1) + 44*Self(n-2) - 370*Self(n-3) - 240*Self(n-4) + 2400*Self(n-5): n in [1..50]]; // G. C. Greubel, Oct 12 2018
(GAP) a:=[1, 1, 31, 134, 2094];; for n in [6..20] do a[n]:=10*a[n-1]+44*a[n-2]-370*a[n-3]-240*a[n-4]+2400*a[n-5]; od; a; # Muniru A Asiru, Oct 12 2018

Crossrefs

Sequence in context: A044744 A167388 A250462 * A142561 A165568 A141950

Adjacent sequences: A123233 A123234 A123235 * A123237 A123238 A123239

Keyword

nonn,easy

Author

Roger L. Bagula, Oct 06 2006

Extensions

Edited by N. J. A. Sloane, Oct 08 2006

Status

approved