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A241049 Smallest number k such that sopf(k)/digsum(k) = prime(n) where sopf(k) is the sum of the distinct primes dividing k and digsum(k) the sum of digits of k. 1
42, 104, 130, 10, 212, 1336, 1630, 1003, 1556, 3122, 2455, 5298, 9105, 13842, 3241, 5230, 10020, 8754, 11671, 10104, 16305, 13141, 7628, 12786, 16201, 2012, 18007, 10630, 11965, 12607, 13945, 14623, 38234, 24343, 30823, 24020, 7846, 17905, 11348, 12061, 27517 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(n) is the smallest k such that A008472(k)/ A007953(k) = prime(n).

LINKS

Michel Lagneau, Table of n, a(n) for n = 1..200

EXAMPLE

a(7) = 1630 because A008472(1630)/ A007953(1630) = 170/10 = 17 = prime(7).

MATHEMATICA

lst={}; Do[k=1; While[Plus @@ First[ Transpose[ FactorInteger[k]]]/

Plus@@IntegerDigits[k]!=Prime[n], k++]; AppendTo[lst, k], {n, 1, 42}]; lst

CROSSREFS

Cf. A008472, A007953.

Sequence in context: A172465 A235109 A039470 * A075296 A023716 A045148

Adjacent sequences:  A241046 A241047 A241048 * A241050 A241051 A241052

KEYWORD

nonn,base

AUTHOR

Michel Lagneau, Apr 15 2014

STATUS

approved

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Last modified January 26 06:32 EST 2021. Contains 340434 sequences. (Running on oeis4.)