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A140470
Numbers n such that p+1 divides n for every prime p that divides n.
4
1, 12, 24, 36, 48, 60, 72, 96, 108, 120, 132, 144, 168, 180, 192, 216, 240, 264, 288, 300, 324, 336, 360, 384, 396, 432, 480, 504, 528, 540, 552, 576, 600, 612, 648, 660, 672, 720, 768, 792, 840, 864, 900, 960, 972, 1008, 1056, 1080, 1104, 1140, 1152, 1176
OFFSET
1,2
COMMENTS
Every term is a multiple of 12.
LINKS
MATHEMATICA
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 *)
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 *)
PROG
(Haskell)
a140470 n = a140470_list !! (n-1)
a140470_list = filter
(\x -> all (== 0) $ map ((mod x) . (+ 1)) $ a027748_row x) [1..]
-- Reinhard Zumkeller, Aug 27 2013
CROSSREFS
KEYWORD
nonn
AUTHOR
Leroy Quet, Jun 28 2008
EXTENSIONS
More terms from Stefan Steinerberger, Jul 01 2008
a(1)=1 prepended by Max Alekseyev, Aug 27 2013
STATUS
approved