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Number of Dyck paths of semilength n avoiding the consecutive step pattern given by the binary expansion of n, where 1=U=(1,1) and 0=D=(1,-1).
3

%I #7 Jun 10 2014 04:54:25

%S 1,0,0,1,1,9,1,127,323,1515,4191,10455,20705,93802,113634,3219205,

%T 10626023,45980364,139604903,555857157,1334821448,7577098816,

%U 20676558270,61994003643,193904367362,800928670232,2374027931492,12506574770693,29311991924792

%N Number of Dyck paths of semilength n avoiding the consecutive step pattern given by the binary expansion of n, where 1=U=(1,1) and 0=D=(1,-1).

%H Alois P. Heinz, <a href="/A243754/b243754.txt">Table of n, a(n) for n = 0..512</a>

%e a(5) = 9 because there are 9 Dyck paths of semilength 5 avoiding the consecutive step pattern UDU given by the binary expansion of 5 = 101_2: UUDDUUDDUD, UUDDUUUDDD, UUUDDDUUDD, UUUDDUDDUD, UUUDDUUDDD, UUUUDDDDUD, UUUUDDDUDD, UUUUDDUDDD, UUUUUDDDDD.

%e a(6) = 1: UDUDUDUDUDUD.

%Y Column k=0 of A243752.

%Y Main diagonal of A243753.

%K nonn

%O 0,6

%A _Alois P. Heinz_, Jun 09 2014