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A075657 Numbers n such that sum of digits (A007953) is a divisor of sum of prime divisors (A008472). 9
2, 3, 5, 7, 10, 42, 70, 84, 91, 100, 104, 110, 114, 115, 130, 143, 148, 154, 160, 170, 182, 185, 212, 215, 221, 222, 228, 230, 234, 238, 250, 266, 295, 304, 312, 326, 336, 372, 402, 412, 425, 437, 460, 468, 485, 494, 516, 555, 558, 583, 700, 702, 721, 730 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000

EXAMPLE

digsum(10) = 1 + 0 = 1, PrimeDivisors(10) = PrimeDivisors(2 *5) = {2,5} and sopf(10) = 2 + 5 = 7 = 7*1.

digsum(154) = 1 + 5 + 4 = 10, PrimeDivisors(154) = PrimeDivisors(2 * 7 * 11) = {2,7,11} and sopf(154) = 2+7+11 = 20 = 2*10.

MATHEMATICA

Select[Range[2, 800], Divisible[Total[Select[Divisors[#], PrimeQ]], Total[ IntegerDigits[#]]]&] (* Harvey P. Dale, Sep 23 2012 *)

PROG

(MAGMA) [m:m in [2..730]| &+PrimeDivisors(m) mod &+Intseq(m) eq 0]; // Marius A. Burtea, Jul 11 2019

CROSSREFS

Sequence in context: A283809 A104622 A033843 * A039711 A194261 A194262

Adjacent sequences:  A075654 A075655 A075656 * A075658 A075659 A075660

KEYWORD

nonn,base

AUTHOR

Floor van Lamoen, Sep 23 2002 and Sep 30 2002

STATUS

approved

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Last modified October 17 18:51 EDT 2019. Contains 328127 sequences. (Running on oeis4.)