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a(n) = a(n-1) + a(n-3) + a(n-4), n >= 4.
2

%I #16 Mar 06 2024 15:45:02

%S 1,-1,2,3,3,4,9,15,22,35,59,96,153,247,402,651,1051,1700,2753,4455,

%T 7206,11659,18867,30528,49393,79919,129314,209235,338547,547780,

%U 886329,1434111,2320438,3754547,6074987,9829536,15904521,25734055,41638578,67372635

%N a(n) = a(n-1) + a(n-3) + a(n-4), n >= 4.

%C See comment and FAMP code for A111569.

%C Floretion Algebra Multiplication Program, FAMP Code: -4baseiseq[B+H] with B = - .25'i + .25'j - .25i' + .25j' + k' - .5'kk' - .25'ik' - .25'jk' - .25'ki' - .25'kj' - .5e and H = + .75'ii' + .75'jj' + .75'kk' + .75e

%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (1, 0, 1, 1).

%F G.f.: (-1+2*x-3*x^2)/((x^2+x-1)*(x^2+1)).

%t LinearRecurrence[{1,0,1,1},{1,-1,2,3},40] (* _Harvey P. Dale_, Jan 24 2017 *)

%Y Cf. A001638, A111569, A111570, A111571, A111572, A111573, A111575, A111576.

%K easy,sign

%O 0,3

%A _Creighton Dement_, Aug 10 2005