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A variant of the recurrence for A001190.
2

%I #5 Mar 30 2012 16:47:49

%S 0,1,1,1,2,2,5,7,17,29,66,126,284,568,1281,2662,6017,12756,28992,

%T 62621,142801,312129,714760,1578706,3626762,8074580,18606900,41716797,

%U 96374235,217271226,503159109,1139963936,2645397326,6018491701

%N A variant of the recurrence for A001190.

%p A038750 := proc(n) option remember; local s,k; if n<=1 then RETURN(n); elif n <=3 then RETURN(1); else s := 0; if n mod 2 = 0 then s := A038750(n/2)*(A038750(n/2)+1)/2; for k from 1 to n/2-1 do s := s+A038750(k)*A038750(n-k); od; RETURN(s); else for k from 1 to (n-1)/2-1 do s := s+A038750(k)*A038750(n-k); od; RETURN(s); fi; fi; end;

%Y Cf. A001190, A038751.

%K nonn

%O 0,5

%A _N. J. A. Sloane_, May 03 2000