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%I #8 Mar 22 2017 03:35:15
%S 10001,12,40,32,240,3040,2240,1152,6400,12800,21504,440320,2140160,
%T 172032,4710400,1802240,1327104,20316160,40632320,17301504,152043520,
%U 602931200,138412032,117440512,3607101440,1132462080,51204063232,3355443200,35232153600,202400333824,102005473280
%N a(n) is the least number having sum of digits n in base 10 and also exactly n prime factors (counted with multiplicity).
%e a(2)=10001 since 1+0+0+0+1=2 and 10001=73*137 has 2 prime factors.
%e a(3)=12 since 1+2=3 and 12=2*2*3 has 3 prime factors.
%t Lk[n_] := Block[{k = 2}, While[n != Plus @@ IntegerDigits[k] || n != Plus @@ (Transpose[FactorInteger@k][[2]]), k++ ]; k]; L = {}; Do[v = Lk[n]; Print[{n, v}]; AppendTo[L, v], {n, 2, 13}]; L
%Y Cf. A115156.
%K base,nonn
%O 2,1
%A _Giovanni Resta_, Jan 18 2006
%E a(23)-a(28) from _Donovan Johnson_, Nov 15 2009
%E a(29)-a(32) from _Giovanni Resta_, Mar 21 2017
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