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A249765 Numbers that divide the concatenation, in descending order, of their anti-divisors. 0
7, 23957, 56483, 74651, 316782, 13594764, 14473747, 30056837 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
EXAMPLE
Anti-divisors of 7 are and 2, 3, 5 and their concatenation in descending order is 532. Finally, 532 / 7 = 76.
MAPLE
P:=proc(q) local a, k, n; for n from 3 to q do a:=0;
for k from n-1 by -1 to 2 do if abs((n mod k)-k/2)<1 then a:=a*10^(ilog10(k)+1)+k; fi; od;
if type(a/n, integer) then print(n); fi; od; end: P(10^9);
CROSSREFS
Sequence in context: A351326 A285178 A072050 * A201037 A300200 A156169
KEYWORD
nonn,base,hard,more
AUTHOR
Paolo P. Lava, Nov 06 2014
EXTENSIONS
a(5)-a(8) from Chai Wah Wu, Nov 21 2014
STATUS
approved

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Last modified April 13 15:05 EDT 2024. Contains 371644 sequences. (Running on oeis4.)