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Numbers of form m*k with m+1 <= k <= 2m-1.
4

%I #18 Oct 07 2018 12:56:38

%S 6,12,15,20,24,28,30,35,40,42,45,48,54,56,60,63,66,70,72,77,80,84,88,

%T 90,91,96,99,104,108,110,112,117,120,126,130,132,135,140,143,144,150,

%U 153,154,156,160,165,168,170,176,180,182,187,190,192,195,198,204,208,209,210,216,220,221,224,228,231

%N Numbers of form m*k with m+1 <= k <= 2m-1.

%H Charles R Greathouse IV, <a href="/A001284/b001284.txt">Table of n, a(n) for n = 1..10000</a>

%o (PARI) list(lim)=my(v=List()); for(m=2,sqrt(lim), for(k=m+1,min(lim\m,2*m-1), listput(v,m*k))); Set(v) \\ _Charles R Greathouse IV_, Oct 23 2015

%Y Subsequence of A005279.

%K nonn,easy

%O 1,1

%A _N. J. A. Sloane_

%E Terms a(45) and beyond, and offset corrected by _Charles R Greathouse IV_, Oct 23 2015