A113760 - OEIS

%I #4 Oct 19 2017 03:14:59

%S 20,30,2002,100130,30030,11030110,1010011310,21020110020,

%T 10030101101020,3003001000200110,1010211202010010,

%U 10020011010010010210110

%N a(n) is the least number having sum of digits n in base 10 and also exactly n distinct prime factors.

%e a(2)=20 since 2+0=2 and 20=2^2*5 has 2 distinct prime factors.

%e a(5)=100130 since 1+0+0+1+3+0=5 and 100130=2*5*17*19*31 has 5 distinct prime factors.

%t Lk[n_] := Block[{k = 2}, While[n != Plus @@ IntegerDigits[k] || n != Length@FactorInteger@k, k++ ]; k]; L = {}; Do[v = Lk[n]; Print[{n, v}]; AppendTo[L, v], {n, 2, 5}]; L

%K base,hard,more,nonn

%O 2,1

%A _Giovanni Resta_, Jan 18 2006

%E More terms from _Don Reble_, Oct 26 2006