Search: id:A023428 Results 1-1 of 1 results found. %I A023428 %S A023428 1,1,1,1,1,1,2,4,7,11,17,27,45,77,132,224,378,640, %T A023428 1093,1881,3250,5622,9732,16874,29332,51126,89313, %U A023428 156283,273842,480474,844220,1485472,2617335,4617243 %N A023428 Generalized Catalan Numbers. %t A023428 Clear[ a ]; a[ 0 ]=1; a[ n_Integer ] := a[ n ]=a[ n-1 ]+Sum[ a[ k ]*a[ n-4-k ], {k, 2, n-4} ]; %Y A023428 Cf. A000108, A001006, A004148, A006318. %Y A023428 Sequence in context: A005252 A023430 A023429 this_sequence A093911 A152398 A023427 %Y A023428 Adjacent sequences: A023425 A023426 A023427 this_sequence A023429 A023430 A023431 %K A023428 nonn,easy %O A023428 0,7 %A A023428 Olivier Gerard (olivier.gerard(AT)gmail.com) Search completed in 0.001 seconds