A192811 a(n) = A192809(n)/2.

0, 0, 1, 7, 37, 183, 893, 4351, 21205, 103367, 503917, 2456655, 11976517, 58387095, 284644701, 1387679903, 6765119669, 32980836455, 160785858381, 783851928559, 3821379890981, 18629722961207, 90822317465149, 442770585849407

Offset

0,4

Links

G. C. Greubel, Table of n, a(n) for n = 0..1000

Index entries for linear recurrences with constant coefficients, signature (7,-12,8).

Formula

a(n) = 7*a(n-1) - 12*a(n-2) + 8*a(n-3).

G.f.: x^2/(1-7*x+12*x^2-8*x^3). - Colin Barker, Jul 26 2012

Mathematica

(See A192808.)
LinearRecurrence[{7, -12, 8}, {0, 0, 1}, 30] (* Harvey P. Dale, Dec 06 2018 *)

Prog

(PARI) my(x='x+O('x^30)); concat([0, 0], Vec(x^2/(1-7*x+12*x^2-8*x^3))) \\ G. C. Greubel, Jan 03 2019
(Magma) m:=30; R<x>:=PowerSeriesRing(Integers(), m); [0, 0] cat Coefficients(R!( x^2/(1-7*x+12*x^2-8*x^3) )); // G. C. Greubel, Jan 03 2019
(Sage) (x^2/(1-7*x+12*x^2-8*x^3)).series(x, 30).coefficients(x, sparse=False) # G. C. Greubel, Jan 03 2019
(GAP) a:=[0, 0, 1];; for n in [4..25] do a[n]:=7*a[n-1]-12*a[n-2]+8*a[n-3]; od; Print(a); # Muniru A Asiru, Jan 03 2019

Crossrefs

Cf. A192232, A192744, A192809.

Sequence in context: A026889 A356338 A117424 * A037546 A226867 A140476

Adjacent sequences: A192808 A192809 A192810 * A192812 A192813 A192814

Keyword

nonn,easy

Author

Clark Kimberling, Jul 10 2011

Extensions

Name corrected by Colin Barker, Jul 26 2012

Status

approved