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%I #14 Aug 03 2014 14:01:35
%S 2,4,8,88,888,222222,444444,888888,444444444444,888888888888,
%T 444444444444444444,888888888888888888,888888888888888888888888,
%U 222222222222222222222222222222,444444444444444444444444444444,888888888888888888888888888888
%N Smallest number with all identical digits having n prime factors with multiplicity.
%F min{ A010785(k): A001222(A010785(k)) = n}. - R. J. Mathar, Nov 03 2011
%e a(7) = 444444 = 2^2*3*7*11*13*37 has 7 prime factors with multiplicity, hence 444444 is in the sequence.
%p with(numtheory):for n from 1 to 17 do:i:=0:for k from 1 to 60 while(i=0)do:for a from 1 to 9 while(i=0)do:x:=((10^k- 1)/9)*a:if bigomega(x)=n then i:=1:printf(`%d, `,x):else fi:od:od:od:
%t Table[digs = 1; While[i = 1; While[num = FromDigits[Table[i, {digs}]]; stop = (i > 9) || PrimeOmega[num] == n; ! stop, i++]; i > 9, digs++]; num, {n, 16}] (* _T. D. Noe_, Nov 03 2011 *)
%Y Cf. A087331.
%K nonn,base
%O 1,1
%A _Michel Lagneau_, Nov 03 2011