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Triangle with columns built from certain power sequences.
10

%I #21 Sep 30 2022 23:30:29

%S 1,2,1,4,3,1,8,12,4,1,16,48,24,5,1,32,192,144,40,6,1,64,768,864,320,

%T 60,7,1,128,3072,5184,2560,600,84,8,1,256,12288,31104,20480,6000,1008,

%U 112,9,1,512,49152,186624,163840,60000,12096,1568,144,10,1

%N Triangle with columns built from certain power sequences.

%H Indranil Ghosh, <a href="/A067410/b067410.txt">Rows 0..125, flattened</a>

%F a(n, m) = 1 if n = m; a(n, m) = (m+2)*(2*(m+1))^(n-m-1) if n > m >= 0.

%F G.f. for column m: (x^m)*(1-m*x)/(1-2*(m+1)*x).

%e Triangle starts:

%e 1;

%e 2, 1;

%e 4, 3, 1;

%e 8, 12, 4, 1;

%e ...

%t A[n_,m_]:=If[n==m,1,(m+2)(2(m+1))^(n-m-1)]; Flatten[Table[A[n,m],{n,0,9},{m,0,n}]] (* _Stefano Spezia_, Sep 30 2022 *)

%Y Cf. A009998 (triangle built from powers of (m+1)), A067402.

%Y Columns m=0..8 are A000079, A002001, A067411, A067412, A090019, A067413, A067414, A067415, A067416.

%K nonn,easy,tabl

%O 0,2

%A _Wolfdieter Lang_, Jan 25 2002