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 A241268 Numbers n such that (n+1)^7-n^7 is not prime. 1
 2, 4, 5, 10, 12, 13, 14, 15, 17, 18, 19, 20, 21, 22, 23, 24, 26, 27, 28, 29, 30, 31, 33, 34, 36, 37, 39, 41, 42, 43, 44, 45, 46, 47, 49, 51, 52, 53, 55, 56, 57, 59, 60, 61, 62, 63, 64, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 80, 81, 82, 83, 84, 85, 86, 88 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Vincenzo Librandi, Table of n, a(n) for n = 1..10000 EXAMPLE 4 is in this sequence because 5^7 - 4^7 = 61741 = 29*2129. MATHEMATICA Select[Range[100], ! PrimeQ[(# + 1)^7 - #^7] &] PROG (Magma) [n: n in [0..350] | not IsPrime((n+1)^7-n^7)]; CROSSREFS Complement of A113826. Sequence in context: A083416 A022770 A141481 * A285697 A047611 A325095 Adjacent sequences: A241265 A241266 A241267 * A241269 A241270 A241271 KEYWORD nonn,easy AUTHOR Vincenzo Librandi, Apr 20 2014 STATUS approved

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Last modified November 29 06:17 EST 2023. Contains 367422 sequences. (Running on oeis4.)