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 A187554 Odd nonprimes n such that n+d+1 is prime for all divisors d of n. 1
 1, 9, 35, 39, 65, 125, 749, 755, 905, 935, 989, 1469, 1829, 1859, 2519, 3161, 4269, 4859, 5165, 5699, 6005, 7319, 8309, 8759, 9155, 9869, 11129, 12819, 12851, 14141, 14279, 15539, 15899, 18689, 19859, 20019, 25115, 25535, 26679, 28049 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Harvey P. Dale, Table of n, a(n) for n = 1..1000 FORMULA A120776(a(n+1)) = A120806(a(n+1)). EXAMPLE a(6) = 125 with divisors (1, 5, 25, 125) and the set of all n+d+1 is (127, 131, 151, 251) and these are all prime. MATHEMATICA Select[Range[1, 29001, 2], !PrimeQ[#]&&AllTrue[#+Divisors[#]+1, PrimeQ]&] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Aug 21 2016 *) CROSSREFS Cf. A120776, A120806, A120811. Sequence in context: A119757 A003865 A265377 * A338010 A267702 A339995 Adjacent sequences: A187551 A187552 A187553 * A187555 A187556 A187557 KEYWORD nonn AUTHOR Juri-Stepan Gerasimov, Mar 26 2011 STATUS approved

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Last modified August 12 13:41 EDT 2024. Contains 375113 sequences. (Running on oeis4.)