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A074112
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Let omega(m) be the number of distinct prime divisors of m. Then a(n) is the largest n-digit squarefree number such that omega(n) > omega(j) for all j < n.
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2
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6, 78, 966, 9870, 99330, 930930, 9699690, 99953490, 999068070, 9592993410, 99978788910, 999890501610, 9814524629910, 99999887777790, 998448347106210, 9999999768941490, 99992911041433410, 997799870344687410, 9999839051940347610, 99987077573596883670
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OFFSET
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1,1
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LINKS
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MAPLE
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option remember;
local a, o, wrks, j ;
if n = 1 then
return 6;
end if;
for a from 10^n-1 to 10^(n-2) by -1 do
if numtheory[issqrfree](a) then
o := omega(a) ;
wrks := true;
for j from 1 to n-1 do
if omega(procname(j)) >= o then
wrks := false;
break;
end if;
end do:
if wrks then
return a;
end if;
end if;
end do:
return -1 ;
end proc:
for j from 1 do
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CROSSREFS
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KEYWORD
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base,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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