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A113760 a(n) is the least number having sum of digits n in base 10 and also exactly n distinct prime factors. 0
20, 30, 2002, 100130, 30030, 11030110, 1010011310, 21020110020, 10030101101020, 3003001000200110, 1010211202010010, 10020011010010010210110 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,1

LINKS

Table of n, a(n) for n=2..13.

EXAMPLE

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

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

MATHEMATICA

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

CROSSREFS

Sequence in context: A181639 A166631 A167360 * A053679 A158844 A077340

Adjacent sequences:  A113757 A113758 A113759 * A113761 A113762 A113763

KEYWORD

base,hard,more,nonn

AUTHOR

Giovanni Resta, Jan 18 2006

EXTENSIONS

More terms from Don Reble, Oct 26 2006

STATUS

approved

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Last modified February 24 00:38 EST 2020. Contains 332195 sequences. (Running on oeis4.)