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A140470

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

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

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

COMMENTS

Every term is a multiple of 12.

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

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

Cf. A027748, A124240, A141766.

Sequence in context: A033024 A044837 A033009 * A141766 A364710 A367338

Adjacent sequences: A140467 A140468 A140469 * A140471 A140472 A140473

KEYWORD

nonn