A140649 - OEIS

%I #11 Apr 11 2013 02:56:32

%S 1,0,2,1,0,4,2,1,0,8,4,2,1,0,16,8,4,2,1,0,32,16,8,4,2,1,0,64,32,16,8,

%T 4,2,1,0,128,64,32,16,8,4,2,1,0,256,128,64,32,16,8,4,2,1,0,512,256,

%U 128,64,32,16,8,4,2,1,0,1024,512,256,128,64,32,16,8,4,2,1,0,2048,1024,512,256,128,64,32,16,8,4,2,1,0,4096

%N Triangle whose rows are decreasing powers of 2, followed by 0.

%F T(n,k) = 2^(n-k-1) if n>k, otherwise 0.

%e Triangle begins

%e 1, 0,

%e 2, 1, 0,

%e 4, 2, 1, 0,

%e 8, 4, 2, 1, 0,

%e 16, 8, 4, 2, 1, 0,

%e 32, 16, 8, 4, 2, 1, 0,

%e 64, 32, 16, 8, 4, 2, 1, 0

%o (PARI) T(n,k) = if(n>k,2^(n-k-1),0);

%o for(n=2,10,for(k=1,n,print1(T(n,k),", "));print()); /* show triangle */

%K nonn,easy,tabf

%O 2,3

%A _Paul Curtz_, Jul 09 2008