%I #23 Feb 02 2025 06:16:51
%S 4,19,23,42,65,107,172,279,451,730,1181,1911,3092,5003,8095,13098,
%T 21193,34291,55484,89775,145259,235034,380293,615327,995620,1610947,
%U 2606567,4217514,6824081,11041595,17865676,28907271,46772947,75680218,122453165,198133383
%N Fibonacci sequence beginning 4, 19.
%H Tanya Khovanova, <a href="http://www.tanyakhovanova.com/RecursiveSequences/RecursiveSequences.html">Recursive Sequences</a>
%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (1,1).
%F G.f.: (4+15*x)/(1-x-x^2). - _Philippe Deléham_, Nov 19 2008
%p a:= n-> (<<0|1>, <1|1>>^n. <<4, 19>>)[1,1]:
%p seq(a(n), n=0..50); # _Alois P. Heinz_, Nov 18 2018
%t a={};b=4;c=19;AppendTo[a, b];AppendTo[a, c];Do[b=b+c;AppendTo[a, b];c=b+c;AppendTo[a, c], {n, 4!}];a (* _Vladimir Joseph Stephan Orlovsky_, Sep 17 2008 *)
%t LinearRecurrence[{1, 1}, {4, 19}, 36] (* _Jean-François Alcover_, Feb 02 2025 *)
%Y Cf. A000045.
%K nonn,easy,changed
%O 0,1
%A _N. J. A. Sloane_