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Smallest number of the form 11*m+1 with exactly n prime factors, counted with multiplicity.
1

%I #17 Feb 03 2023 01:35:49

%S 1,23,34,12,56,243,144,320,2432,1728,1024,17920,20736,12288,57344,

%T 248832,147456,327680,2490368,1769472,1048576,18350080,21233664,

%U 12582912,58720256,254803968,150994944,335544320,2550136832,1811939328,1073741824,18790481920

%N Smallest number of the form 11*m+1 with exactly n prime factors, counted with multiplicity.

%F a(n) = a(n-10)*2^10 for n >= 13.

%e The smallest number of the form 11*m+1 with exactly 8 prime factors is 2^7*19 = 11*221+1 = 2432.

%t Join[{1}, Table[k = 1; While[Total[Transpose[FactorInteger[11*k + 1]][[2]]] != n, k++]; 11*k + 1, {n, 20}]] (* _T. D. Noe_, Oct 10 2013 *)

%K nonn

%O 0,2

%A _Elliott Line_, Oct 10 2013