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%I #10 Aug 08 2015 21:58:55
%S 1,2,9,55,448,5533,77753,1415862,28378685,685274581,20695944714,
%T 662817798145,25290008485783,1064065877641048,46842303103453733,
%U 2251599342111454707,121817407196390147320,7320071385771594519593
%N a(-1)=0, a(0)=1 and recursively a(n) = prime(n)*(a(n-1)+a(n-2)).
%p A109366 := proc(n) if n<= 0 then n+1; else ithprime(n)*(procname(n-1)+procname(n-2)) ; end if; end proc:
%p seq(A109366(n),n=0..20) ; # _R. J. Mathar_, Sep 15 2011
%Y Cf. A109365.
%K nonn
%O 0,2
%A _Giorgio Balzarotti_, Aug 23 2005