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 A192284 Numbers n such that the average of the anti-divisors of n is an integer. 2
 3, 4, 6, 8, 9, 11, 15, 16, 18, 19, 20, 26, 29, 30, 34, 36, 37, 38, 47, 49, 51, 63, 64, 68, 69, 82, 93, 94, 95, 96, 106, 117, 120, 121, 131, 134, 135, 141, 155, 169, 174, 186, 187, 190, 191, 197, 200, 203, 206, 224, 226, 244, 252, 257, 271, 272, 274, 276, 289 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Like A003601 but using anti-divisors LINKS Paolo P. Lava, Table of n, a(n) for n = 1..1000 EXAMPLE Anti-divisors of 38 are 7: 3, 4, 5, 7, 11, 15, 25. Their sum is 70 and 70/7=10 that is integer. MAPLE with(numtheory); P:=proc(n) local a, b, i, k; for i from 3 to n do a:=0; b:=0; for k from 2 to i-1 do if abs((i mod k)- k/2) < 1 then a:=a+k; b:=b+1; fi; od; if trunc(a/b)=a/b then print(i); fi; od; end: P(1000); CROSSREFS Cf. A003601, A066272 Sequence in context: A000592 A138924 A188015 * A024324 A255773 A195019 Adjacent sequences: A192281 A192282 A192283 * A192285 A192286 A192287 KEYWORD nonn AUTHOR Paolo P. Lava, Jul 20 2011 STATUS approved

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Last modified May 30 20:23 EDT 2023. Contains 363061 sequences. (Running on oeis4.)