%I A091345
%S A091345 0,0,2,30,398,5430,79022,1238790,20944478,381167670,7443745742,
%T A091345 155454939750,3459933837758,81801569650710,2048133412585262,
%U A091345 54153668865539910,1508122968767710238,44130728380569410550
%N A091345 Exponential convolution of A069321(n) with itself, where we set A069321(0)=0.
%F A091345 a(n)=Sum(C(n, k)Sum(i!i Stirling2(k, i), i=1, .., k)Sum(i!i Stirling2(n-k, 
               i), i=1, .., n-k), k=0, .., n)
%t A091345 Table[ Sum[Binomial[n, k]Sum[i!i StirlingS2[k, i], {i, 1, k}]Sum[i!i 
               StirlingS2[n - k, i], {i, 1, n - k}], {k, 0, n}], {n, 0, 20}]
%Y A091345 Sequence in context: A089433 A152277 A083446 this_sequence A147682 A077517 
               A060042
%Y A091345 Adjacent sequences: A091342 A091343 A091344 this_sequence A091346 A091347 
               A091348
%K A091345 easy,nonn
%O A091345 0,3
%A A091345 Mario Catalani (mario.catalani(AT)unito.it), Jan 01 2004