%I A048887
%S A048887 1,1,1,1,2,1,1,2,3,1,1,2,4,5,1,1,2,4,7,8,1,1,2,4,8,13,13,1,1,2,4,8,15,
%T A048887 24,21,1,1,2,4,8,16,29,44,34,1,1,2,4,8,16,31,56,81,55,1,1,2,4,8,16,32,
%U A048887 61,108,149,89,1,1,2,4,8,16,32,63,120
%N A048887 Array T by antidiagonals, where T(m,n)=number of compositions of n into
parts all <=m.
%D A048887 J. Riordan, An Introduction to Combinatorial Analysis, Princeton University
Press, Princeton, NJ, 1978, p. 154.
%F A048887 G.f.: (1-z)/[1-2z+z^(t+1)].
%e A048887 T(2,5) counts 11111,1112,1121,1211,2111,122,212,221, where "1211" abbreviates
the composition 1+2+1+1. The array begins:
%e A048887 1,1,1,1,1,1,1,...
%e A048887 1,2,3,5,8,13,...
%e A048887 1,2,4,7,13,...
%e A048887 1,2,4,8,...
%p A048887 G := t->(1-z)/(1-2*z+z^(t+1)): T := (m,n)->coeff(series(G(m),z=0,30),
z^n): matrix(7,12,T);
%Y A048887 Rows: A000045 (Fibonacci), A000073 (tribonacci), A000078 (Tetranacci),
etc.
%Y A048887 Essentially a reflected version of A092921. See A048004 and A126198 for
closely related arrays.
%Y A048887 Sequence in context: A104763 A027751 A004070 this_sequence A047913 A117935
A103462
%Y A048887 Adjacent sequences: A048884 A048885 A048886 this_sequence A048888 A048889
A048890
%K A048887 nonn,tabl
%O A048887 1,5
%A A048887 Clark Kimberling (ck6(AT)evansville.edu)
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