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 A094520 Numbers such that all sums of two distinct divisors are not divisors. 3
 1, 2, 3, 4, 5, 7, 8, 9, 10, 11, 13, 14, 15, 16, 17, 19, 21, 22, 23, 25, 26, 27, 28, 29, 31, 32, 33, 34, 35, 37, 38, 39, 41, 43, 44, 45, 46, 47, 49, 50, 51, 52, 53, 55, 57, 58, 59, 61, 62, 63, 64, 65, 67, 68, 69, 71, 73, 74, 75, 76, 77, 79, 81, 82, 83, 85, 86, 87, 88, 89, 91 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Amiram Eldar, Table of n, a(n) for n = 1..10000 Eric Weisstein's World of Mathematics, Sum-Free Set FORMULA A094518(a(n)) = 0. MATHEMATICA aQ[n_] := AllTrue[Total /@ Subsets[Divisors[n], {2}], ! Divisible[n, #] &]; Select[Range[91], aQ] (* Amiram Eldar, Aug 31 2019 *) CROSSREFS Cf. A094518. Complement of A094519. Sequence in context: A320340 A228869 A088725 * A136447 A005100 A051772 Adjacent sequences:  A094517 A094518 A094519 * A094521 A094522 A094523 KEYWORD nonn AUTHOR Reinhard Zumkeller, May 06 2004 STATUS approved

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Last modified November 25 20:53 EST 2020. Contains 338627 sequences. (Running on oeis4.)