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%I #8 Apr 09 2014 10:16:30
%S 1,1,1,1,4,10,28,190,3052,123196,27522064,89625932920,
%T 11318569384820032,312907271203608153807520,
%U 28053218967767813941001154374119168,317524819653692484884273872549799784105586335582976
%N a(1)=a(2)=a(3)=a(4)=1. For n >= 5, a(n)= (a(n-1)+a(n-2)) * (a(n-3)+a(n-4)).
%t RecurrenceTable[{a[1]==a[2]==a[3]==a[4]==1,a[n]==(a[n-1]+a[n-2]) (a[n-3]+ a[n-4])},a[n],{n,20}](* _Harvey P. Dale_, Aug 08 2011 *)
%o (PARI) a(n)=if(n<5,1,(a(n-1)+a(n-2)) *(a(n-3)+a(n-4))) (Klasen)
%K easy,nonn
%O 1,5
%A _Leroy Quet_, Oct 28 2005
%E More terms from Lambert Klasen (lambert.klasen(AT)gmx.net), Oct 31 2005
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