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A268417
Numbers other than prime powers divisible by the sum and the sum of squares of their prime divisors.
2
99528, 117040, 143520, 199056, 234080, 287040, 288288, 294216, 298584, 349440, 357357, 383040, 398112, 430560, 468160, 574080, 576576, 585200, 588432, 597168, 631488, 698880, 717600, 766080, 796224, 819280, 861120, 864864, 870870, 882648, 895752, 901824, 936320, 957000
OFFSET
1,1
COMMENTS
Intersection of A066031 and A190882.
Prime divisors taken without multiplicity. - Harvey P. Dale, Dec 27 2018
LINKS
Jean-Marie de Koninck and Florian Luca, Integers divisible by sums of powers of their prime factors, Journal of Number Theory, Volume 128, Issue 3, March 2008, Pages 557-563.
MATHEMATICA
dssQ[n_]:=Module[{pf=FactorInteger[n][[All, 1]]}, !PrimePowerQ[ n] && Divisible[ n, Total[pf]]&&Divisible[n, Total[pf^2]]]; Select[ Range[ 960000], dssQ] (* Harvey P. Dale, Dec 27 2018 *)
PROG
(PARI) isok(n) = my(f = factor(n)[, 1]); (#f>2) && ((n % vecsum(f)) == 0) && ((n % sum(k=1, #f, f[k]^2)) == 0);
CROSSREFS
Sequence in context: A348275 A138732 A108224 * A232188 A032428 A370795
KEYWORD
nonn
AUTHOR
Michel Marcus, Feb 04 2016
STATUS
approved