%I A023430
%S A023430 1,1,1,1,1,1,1,1,2,4,7,11,17,27,44,72,118,194,320,528,
%T A023430 871,1439,2385,3965,6605,11017,18399,30771,51538,
%U A023430 86440,145165,244085,410890,692442,1168114,1972470
%N A023430 Generalized Catalan Numbers.
%t A023430 Clear[ a ]; a[ 0 ]=1; a[ n_Integer ] := a[ n ]=a[ n-1 ]+Sum[ a[ k ]*a[ 
               n-4-k ], {k, 4, n-4} ];
%Y A023430 Cf. A000108, A001006, A004148, A006318.
%Y A023430 Sequence in context: A035295 A006999 A005252 this_sequence A023429 A023428 
               A093911
%Y A023430 Adjacent sequences: A023427 A023428 A023429 this_sequence A023431 A023432 
               A023433
%K A023430 nonn,easy
%O A023430 0,9
%A A023430 Olivier Gerard (olivier.gerard(AT)gmail.com)