%I A097341
%S A097341 1,0,2,2,6,14,38,110,342,1134,3990,14830,58006,237998,1021462,4574318,
%T A097341 21325462,103287598,518768406,2697426926,14498316182,80440333998,
%U A097341 460112203798,2710038058862,16418576767126,102212840258094
%N A097341 Sum k=0..floor(n/2), Stirling2(n-k,k)2^k.
%F A097341 a(n)=sum{k=0..floor(n/2), sum{i=0..k, (-1)^(k+i)i^(n-k)/(i!(k-i)!)}2^k 
               }
%Y A097341 Cf. A024427, A097342.
%Y A097341 Sequence in context: A071109 A005310 A002203 this_sequence A142710 A014431 
               A142471
%Y A097341 Adjacent sequences: A097338 A097339 A097340 this_sequence A097342 A097343 
               A097344
%K A097341 easy,nonn
%O A097341 0,3
%A A097341 Paul Barry (pbarry(AT)wit.ie), Aug 05 2004