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%I #1 May 16 2003 03:00:00
%S 0,0,0,2,7,28,108,414,1585,6087,23446,90532,350343,1358437,5276545,
%T 20527950,79976007,311984922,1218474389,4763911699,18643889114,
%U 73029856058,286302435505,1123267533520,4410123312095,17326303720537
%N Highest power of 9 dividing A068943(n) for n>0.
%C Sequence was suggested by the discovery that the digital root of A068943 is 9 for all n>3.
%e a(11)=23446 since f(11,11,11)=9^binomial(12,10) * 6^binomial(15,10) * 3^(18,10) * other terms. this implies a(11)=binomial(12,10) + 1/2*(binomial(15,10)-1 + binomial(18,10)).
%Y Cf. A068943, A068945.
%K nonn
%O 1,4
%A Francois Jooste (phukraut(AT)hotmail.com), Mar 09 2002