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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
OFFSET
1,1
COMMENTS
All terms are in A079523.
LINKS
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
KEYWORD
nonn,base
AUTHOR
STATUS
approved