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A055238
Numbers that are divisible by at least one of their digits in every base.
4
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14, 15, 16, 18, 20, 24, 28, 30, 36, 42, 48, 60, 120
OFFSET
1,2
COMMENTS
This list is probably finite and complete. For example 180 fails at base 23 and 240 fails at bases 21, 31 and 33
EXAMPLE
9 is included because it can be written as 111111111,1001,100,21,14,13,12,11,10 or 9 and in every case there is a digit which divides 9; 11 is not on the list because in base 4 it is written 23 and 11 is not divisible by either 2 or 3.
MATHEMATICA
divQ[n_, base_] := AnyTrue[Select[IntegerDigits[n, base], Positive], Divisible[n, #]&];
okQ[n_] := AllTrue[Range[2, n-1], divQ[n, #]&];
Select[Range[1000], okQ] (* Jean-François Alcover, Nov 07 2019 *)
CROSSREFS
KEYWORD
fini,full,nice,base,nonn
AUTHOR
Henry Bottomley, May 04 2000
STATUS
approved