%I A115137
%S A115137 1,1,7,41,247,1545,9975,66057,446455,3067913,21372919,150618121,
%T A115137 1071841271,7691763721,55600938999,404488323081,2959189475319,
%U A115137 21757613309961,160691417776119,1191577871450121,8868160862158839
%N A115137 Second diagonal of triangle A113647 (called Y(2,1)).
%F A115137 a(n)= b(n) - 2*b(n-1) with b(n):=A062992(n)= A064062(n+1), n>=1. a(0):=1.
%F A115137 G.f.: (1-2*x)*(2*c(2*x)-1)/(1+x) with c(x) g.f. of A000108 (Catalan).
%F A115137 a(n)= A113647(n, n), n>=1.
%e A115137 41=a(3)= A062992(3) - 2*A062992(2) = 67 - 2*13.
%Y A115137 Sequence in context: A141813 A088165 A108983 this_sequence A036730 A080047 
               A125120
%Y A115137 Adjacent sequences: A115134 A115135 A115136 this_sequence A115138 A115139 
               A115140
%K A115137 nonn,easy
%O A115137 0,3
%A A115137 Wolfdieter Lang (wolfdieter.lang_AT_physik_DOT_uni-karlsruhe_DOT_de), 
               Jan 13 2006