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%I #9 Dec 22 2014 02:01:02
%S 0,0,0,0,0,0,1,0,0,0,1,1,0,1,1,0,0,0,0,0,0,0,0,0,0,0,0,1,1,2,1,2,1,1,
%T 0,0,0,1,1,0,2,2,1,2,2,0,1,1,0,0,0,0,0,0,0,1,1,1,0,0,0,0,0,0,0,0,2,0,
%U 0,2,0,0,3,0,0,2,0,0,2,0,0,0,2,2,1,2,2,1,2,2,0,2,2,1,2,2,1,2,2,0,0,0,0,1,1
%N Triangle T(n,k) giving exponent of power of 3 dividing entry (n,k) of trinomial triangle A027907.
%D B. A. Bondarenko, Generalized Pascal Triangles and Pyramids (in Russian), FAN, Tashkent, 1990, ISBN 5-648-00738-8. English translation published by Fibonacci Association, Santa Clara Univ., Santa Clara, CA, 1993; see p. 118.
%e 0; 0,0,0; 0,0,1,0,0; 0,1,1,0,1,1,0; ...
%p with(numtheory): T := proc(i,j) option remember: if i >= 0 and j=0 then RETURN(1) fi: if i >= 0 and j=2*i then RETURN(1) fi: if i >= 1 and j=1 then RETURN(i) fi: if i >= 1 and j=2*i-1 then RETURN(i) fi: T(i-1,j-2)+T(i-1,j-1)+T(i-1,j): end: for i from 0 to 20 do for j from 0 to 2*i do if T(i,j) mod 3 <> 0 then printf(`%d,`,0) fi: if T(i,j) mod 3 = 0 and T(i,j) mod 2 = 0 then printf(`%d,`, ifactors(T(i,j))[2,2,2] ) fi: if T(i,j) mod 3 = 0 and T(i,j) mod 2 = 1 then printf(`%d,`, ifactors(T(i,j))[2,1,2] ) fi: #printf(`%d,`,T(i,j)) od:od: # _James A. Sellers_, Feb 22 2001
%K nonn,easy,tabf
%O 0,30
%A _N. J. A. Sloane_, Feb 22 2001
%E More terms from _James A. Sellers_, Feb 22 2001
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