%I #8 May 13 2019 10:11:57
%S 2,6,17,48,135,379,1064,2987,8385,23538,66075,185483,520680,1461631,
%T 4103029,11517850,32332423,90762215,254783864,715218523,2007731289,
%U 5636018642,15821193955,44412588755,124673147016,349977202919
%N a(n) = 3*a(n-1) - a(n-2) + 2*a(n-3) - 2*a(n-4).
%D R. K. Guy, personal communication.
%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (3,-1,2,-2).
%F G.f.: ( 2+x^2-x^3 ) / ( 1-3*x+x^2-2*x^3+2*x^4 ). - _R. J. Mathar_, Feb 11 2016
%t LinearRecurrence[{3,-1,2,-2},{2,6,17,48},30] (* _Harvey P. Dale_, May 13 2019 *)
%Y Cf. A018915.
%K nonn,easy
%O 0,1
%A _N. J. A. Sloane_.