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%I #15 Jan 16 2022 23:43:22
%S 6,12,18,20,24,30,36,40,42,48,54,56,60,66,72,78,80,84,90,96,100,102,
%T 108,110,112,114,120,126,132,138,140,144,150,156,160,162,168,174,180,
%U 182,186,192,198,200,204,210,216,220,222,224,228,234,240,246,252,258,260
%N Numbers k with at least one divisor d>1 such that d+1 also divides k.
%C A088722(a(n))>0; complement of A088725.
%C Complement of A132895 relative to A005843, the even numbers. - Chandler
%H Reinhard Zumkeller, <a href="/A088723/b088723.txt">Table of n, a(n) for n = 1..10000</a>
%t Select[Range[300],MemberQ[Differences[Select[Divisors[#], #>1&]], 1]&] (* _Harvey P. Dale_, Apr 03 2011 *)
%o (Haskell)
%o a088723 n = a088723_list !! (n-1)
%o a088723_list = filter f [2..] where
%o f x = 1 `elem` (zipWith (-) (tail divs) divs)
%o where divs = tail $ a027750_row x
%o -- _Reinhard Zumkeller_, Dec 16 2013
%Y Cf. A088722, A088724, A088725, A088726.
%Y Cf. A027750, A008588 (subsequence).
%K nonn
%O 1,1
%A _Reinhard Zumkeller_, Oct 12 2003
%E Extended by _Ray Chandler_, May 29 2008
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