%I A049680
%S A049680 2,2,5,11,27,67,170,436,1127,2927,7625,19901,52002,135982,355745,
%T A049680 930931,2436527,6377807,16695530,43706576,114420627,299549527,
%U A049680 784218605,2053091161,5375030402,14071960442,36840786845,96450296411
%N A049680 a(n)=(L(n)+L(2n))/2, where L=A000032 (the Lucas sequence).
%F A049680 Binomial transform of trace(A^n)/4, where A is the adjacency matrix of 
               path graph P_4 (A005248 with interpolated zeros). - Paul Barry (pbarry(AT)wit.ie), 
               Apr 24 2004
%Y A049680 Sequence in context: A078405 A109278 A112527 this_sequence A153983 A058021 
               A152445
%Y A049680 Adjacent sequences: A049677 A049678 A049679 this_sequence A049681 A049682 
               A049683
%K A049680 nonn
%O A049680 0,1
%A A049680 Clark Kimberling (ck6(AT)evansville.edu)