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A113758 a(n) is the least number having sum of digits n in base 10 and also exactly n prime factors (counted with multiplicity). 0
10001, 12, 40, 32, 240, 3040, 2240, 1152, 6400, 12800, 21504, 440320, 2140160, 172032, 4710400, 1802240, 1327104, 20316160, 40632320, 17301504, 152043520, 602931200, 138412032, 117440512, 3607101440, 1132462080, 51204063232, 3355443200, 35232153600, 202400333824, 102005473280 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,1

LINKS

Table of n, a(n) for n=2..32.

EXAMPLE

a(2)=10001 since 1+0+0+0+1=2 and 10001=73*137 has 2 prime factors.

a(3)=12 since 1+2=3 and 12=2*2*3 has 3 prime factors.

MATHEMATICA

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

CROSSREFS

Cf. A115156.

Sequence in context: A250440 A013857 A091566 * A273531 A291312 A203591

Adjacent sequences:  A113755 A113756 A113757 * A113759 A113760 A113761

KEYWORD

base,nonn

AUTHOR

Giovanni Resta, Jan 18 2006

EXTENSIONS

a(23)-a(28) from Donovan Johnson, Nov 15 2009

a(29)-a(32) from Giovanni Resta, Mar 21 2017

STATUS

approved

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Last modified May 30 14:43 EDT 2020. Contains 334725 sequences. (Running on oeis4.)