%I A081078
%S A081078 4,44,319,2204,15124,103679,710644,4870844,33385279,228826124,
%T A081078 1568397604,10749957119,73681302244,505019158604,3461452807999,
%U A081078 23725150497404,162614600673844,1114577054219519,7639424778862804
%N A081078 Lucas(4n)-3, or Lucas(2n-1)*Lucas(2n+1).
%D A081078 Hugh C. Williams, Edouard Lucas and Primality Testing, John Wiley and 
               Sons, 1998, p. 75
%F A081078 a(n) = 8a(n-1)-8a(n-2)+a(n-3)
%F A081078 a(n)=-3+(7/2)*{[(7/2)-(3/2)*sqrt(5)]^n+[(7/2)+(3/2)*sqrt(5)]^n}+(3/2)*sqrt(5)*{[(7/
               2)+(3/2) *sqrt(5)]^n-[(7/2)-(3/2)*sqrt(5)]^n}, with n>=0 [From Paolo 
               P. Lava (ppl(AT)spl.at), Dec 01 2008]
%p A081078 luc := proc(n) option remember: if n=0 then RETURN(2) fi: if n=1 then 
               RETURN(1) fi: luc(n-1)+luc(n-2): end: for n from 1 to 40 do printf(`%d,
               `,luc(4*n)-3) od:
%Y A081078 Cf. A000032 (Lucas numbers).
%Y A081078 Sequence in context: A077435 A074751 A129551 this_sequence A035014 A030987 
               A043039
%Y A081078 Adjacent sequences: A081075 A081076 A081077 this_sequence A081079 A081080 
               A081081
%K A081078 nonn,easy
%O A081078 1,1
%A A081078 R. K. Guy (rkg(AT)cpsc.ucalgary.ca), Mar 04, 2003
%E A081078 More terms and Maple code from James A. Sellers (sellersj(AT)math.psu.edu), 
               Mar 05, 2003