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A134330 Nonprime numbers which are divisible by the sum of their prime factors (counted with multiplicity). 7
1, 4, 16, 27, 30, 60, 70, 72, 84, 105, 150, 180, 220, 231, 240, 256, 286, 288, 308, 378, 440, 450, 476, 528, 540, 560, 576, 588, 594, 624, 627, 646, 648, 650, 728, 800, 805, 840, 884, 897, 900, 945, 960, 1008, 1040, 1056, 1080, 1100, 1122, 1134, 1160, 1170 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Essentially the same as A046346 - R. J. Mathar, Jun 08 2008

LINKS

Table of n, a(n) for n=1..52.

EXAMPLE

a(5)=30, since 30=2*3*5 and 2+3+5=10 divides 30, but 28=2*2*7, where 2+2+7=11 is not a factor of 28 and 29 is a prime.

MATHEMATICA

dspfQ[n_]:=Divisible[n, Total[Flatten[Table[#[[1]], {#[[2]]}]&/@ FactorInteger[ n]]]]; Select[Range[1200], !PrimeQ[#]&&dspfQ[#]&] (* Harvey P. Dale, Aug 25 2015 *)

CROSSREFS

Cf. A000040, A001222, A100118, A046363, A133620, A133621, A133623, A133630, A133635.

Cf. A133872, A133880, A133890, A133900, A133910, A133911, A134331.

Sequence in context: A105078 A050707 A046346 * A097764 A227993 A072873

Adjacent sequences:  A134327 A134328 A134329 * A134331 A134332 A134333

KEYWORD

nonn

AUTHOR

Hieronymus Fischer, Oct 23 2007

EXTENSIONS

Definition corrected by N. J. A. Sloane, Jun 23 2009

STATUS

approved

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Last modified May 24 14:49 EDT 2019. Contains 323532 sequences. (Running on oeis4.)