%I A106469
%S A106469 1,2,2,4,2,4,2,4,2,4,2,4,2,4,2,4,2,4,2,4,2,4,2,4,2,4,2,4,2,4,2,4,2,4,2,
%T A106469 4,2,4,2,4,2,4,2,4,2,4,2,4,2,4,2,4,2,4,2,4,2,4,2,4,2,4,2,4,2,4,2,4,2,4,
%U A106469 2,4,2,4,2,4,2,4,2,4,2,4,2,4,2,4,2,4,2,4,2,4,2,4,2,4
%N A106469 Expansion of (1+x^2)(1+2x)/(1-x^2).
%C A106469 Row sums of number triangle A106468.
%F A106469 a(0)=1, a(n)=(2-0^((n-1)/2))(1-(-1)^n)+(2-0^(n/2))(1+(-1)^n)/2, n>1.
%Y A106469 Sequence in context: A100374 A045841 A040003 this_sequence A082508 A163824 
               A075526
%Y A106469 Adjacent sequences: A106466 A106467 A106468 this_sequence A106470 A106471 
               A106472
%K A106469 easy,nonn
%O A106469 0,2
%A A106469 Paul Barry (pbarry(AT)wit.ie), May 03 2005