%I A127284
%S A127284 0,0,1,0,2,1,1,1,0,3,2,2,2,1,2,1,2,2,1,1,1,1,0,4,3,3,3,2,3,2,3,3,2,2,
%T A127284 2,2,1,3,2,2,2,1,3,2,3,3,2,2,2,2,1,2,1,2,2,1,2,2,2,1,1,1,1,1,0,5,4,4,
%U A127284 4,3,4,3,4,4,3,3,3,3,2,4,3,3,3,2,4,3,4,4,3,3,3,3,2,3,2,3,3,2,3,3,3,2
%N A127284 a(n) = number of valleys (DU-steps) in the Dyck path encoded by A014486(n).
%F A127284 a(0)=0, a(n) = A057514(n)-1.
%e A127284 A014486(2) = 10 (1010 in binary) which encodes Dyck path /\/\ with two 
               peaks and one valley, thus a(2)=1.
%e A127284 A014486(12) = 180 (10110100 in binary) which encodes Dyck path:
%e A127284 ..../\/\...
%e A127284 ./\/....\..
%e A127284 which has two valleys, thus a(12) = 2.
%o A127284 (Scheme:) (define (A127284 n) (if (zero? n) 0 (- (A057514 n) 1)))
%Y A127284 a(A057163(n)) = A126306(n), a(n) = A126306(A057163(n)) for all n. Cf. 
               A057516.
%Y A127284 Sequence in context: A117479 A118404 A089339 this_sequence A120691 A111941 
               A153462
%Y A127284 Adjacent sequences: A127281 A127282 A127283 this_sequence A127285 A127286 
               A127287
%K A127284 nonn
%O A127284 0,5
%A A127284 Antti Karttunen (His-Firstname.His-Surname(AT)gmail.com), Jan 16 2007