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A140470 Numbers n such that p+1 divides n for every prime p that divides n.

%I A140470 #15 May 27 2016 17:42:00
%S A140470 1,12,24,36,48,60,72,96,108,120,132,144,168,180,192,216,240,264,288,
%T A140470 300,324,336,360,384,396,432,480,504,528,540,552,576,600,612,648,660,
%U A140470 672,720,768,792,840,864,900,960,972,1008,1056,1080,1104,1140,1152,1176
%N A140470 Numbers n such that p+1 divides n for every prime p that divides n.
%C A140470 Every term is a multiple of 12.
%H A140470 Reinhard Zumkeller, <a href="/A140470/b140470.txt">Table of n, a(n) for n = 1..10000</a>
%t A140470 a = {}; For[n = 2, n < 1500, n++, b = Select[Range[n], PrimeQ[ # ] && Mod[n, # ] == 0 &]; c = 1; For[d = 1, d < Length[b] + 1, d++, If[Mod[n, b[[d]] + 1] > 0, c = 0; Break]]; If[c == 1, AppendTo[a, n]]]; a (* _Stefan Steinerberger_, Jul 01 2008 *)
%t A140470 eppQ[n_]:=Union[Differences/@Select[Partition[Divisors[n],2,1], PrimeQ[ #[[1]]]&]]=={{1}}; Join[{1},Select[Range[1200],eppQ]] (* _Harvey P. Dale_, May 27 2016 *)
%o A140470 (Haskell)
%o A140470 a140470 n = a140470_list !! (n-1)
%o A140470 a140470_list = filter
%o A140470    (\x -> all (== 0) $ map ((mod x) . (+ 1)) $ a027748_row x) [1..]
%o A140470 -- _Reinhard Zumkeller_, Aug 27 2013
%Y A140470 Cf. A027748, A124240, A141766.
%K A140470 nonn
%O A140470 1,2
%A A140470 _Leroy Quet_, Jun 28 2008
%E A140470 More terms from _Stefan Steinerberger_, Jul 01 2008
%E A140470 a(1)=1 prepended by _Max Alekseyev_, Aug 27 2013