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A046347 Odd composite numbers divisible by the sum of their prime factors (counted with multiplicity). 3
27, 105, 231, 627, 805, 897, 945, 1581, 1755, 2079, 2625, 2967, 3055, 3125, 3861, 4185, 4543, 5355, 5445, 5487, 5967, 6075, 6461, 6525, 6745, 7881, 8085, 8505, 8883, 9555, 9717, 10125, 10647, 10707, 11375, 11385, 12675, 12789, 13005, 13275, 13475 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

T. D. Noe, Table of n, a(n) for n=1..1000

EXAMPLE

897 is a term since 897 = 3 * 13 * 23 and 3 + 13 + 23 = 39 and 897 / 39 = 23.

MATHEMATICA

Select[Range[9, 13500, 2], !PrimeQ[#]&&IntegerQ[#/Total[Times@@@FactorInteger[#]]]&] (* Jayanta Basu, Jun 04 2013 *)

PROG

(PARI) sopfr(n) = {my(f=factor(n)); sum(k=1, #f~, f[k, 1]*f[k, 2]); }

lista(nn) = forcomposite(n=2, nn, if ((n%2) && !(n % sopfr(n)), print1(n, ", ")); ); \\ Michel Marcus, Feb 06 2019

CROSSREFS

Cf. A046346, A046348.

Sequence in context: A036923 A036346 A140376 * A158549 A254319 A044278

Adjacent sequences:  A046344 A046345 A046346 * A046348 A046349 A046350

KEYWORD

nonn,changed

AUTHOR

Patrick De Geest, Jun 15 1998

EXTENSIONS

Name clarified by Michel Marcus, Feb 06 2019

STATUS

approved

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Last modified February 16 21:22 EST 2019. Contains 320199 sequences. (Running on oeis4.)