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 A231558 Odd composite numbers n, such that n, n+d, n*d and n/d are all odious (A000069) for every divisor d of n. 2
 217, 511, 889, 949, 1957, 2041, 2263, 2413, 2869, 3113, 3133, 3481, 3991, 5201, 5761, 7813, 7903, 8071, 8137, 8773, 10519, 10609, 11377, 11879, 12191, 12313, 12871, 15127, 15223, 16177, 19561, 19733, 19879, 21151, 23077, 23233, 23449, 23573, 26221, 27469 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS All terms are in A079523. LINKS Peter J. C. Moses, Table of n, a(n) for n = 1..10000 EXAMPLE Let n=217. Its divisors are {1,7,31,217}. We see that all numbers 217+1=218, 217+7=224, 217+31=248, 217+217=434, 217/1=217, 217/7=31, 217/31=7, 217/217=1, 217*1=217, 217*7=1519, 217*31=6727, 217*217=47089 are odious. Thus 217 is in the sequence. CROSSREFS Cf. A231271, A228436, A000069, A079523. Sequence in context: A038594 A020232 A019422 * A101826 A262052 A020251 Adjacent sequences:  A231555 A231556 A231557 * A231559 A231560 A231561 KEYWORD nonn,base AUTHOR Vladimir Shevelev and Peter J. C. Moses, Nov 11 2013 STATUS approved

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Last modified October 19 21:28 EDT 2019. Contains 328244 sequences. (Running on oeis4.)