%I #24 Sep 28 2019 11:57:43

%S 4,8,16,32,64,126,128,252,256,378,390,504,512,630,756,780,798,882,

%T 1008,1024,1134,1150,1170,1260,1512,1560,1596,1764,1890,1950,2016,

%U 2046,2048,2268,2300,2340,2394,2520,2646,2730,2886,3024,3120,3150,3192,3402,3450

%N Numbers n such that the sum of the smallest and largest prime factors of n divides n.

%C All terms are even. - _Harvey P. Dale_, Sep 03 2015

%C Powers of 2 and numbers of the form 2 * p * (p + 2) * k where p is prime, p+2 isn't and k > 0 is p-smooth. - _David A. Corneth_, Sep 28 2019

%H Amiram Eldar, <a href="/A111073/b111073.txt">Table of n, a(n) for n = 1..10000</a> (terms 1..1000 from Harvey P. Dale)

%e 126 = 2*3^2*7, with smallest and largest prime factors 2 and 7, sum = 9, and 126 is divisible by 9; so 126 is in the sequence.

%t slpdQ[n_]:=Module[{f=Transpose[FactorInteger[n]][[1]]},Divisible[n, Total[ {First[f],Last[f]}]]]; Select[Range[4000],slpdQ] (* _Harvey P. Dale_, Sep 03 2015 *)

%o (PARI) lista(n) = {for (i=2, n, my(fac = factor(i), s = fac[1, 1] + fac[matsize(fac)[1],1]); if (i % s == 0, print1(i, ", ")););} \\ _Michel Marcus_, May 18 2013

%K easy,nonn

%O 1,1

%A _Joseph L. Pe_, Oct 10 2005