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A187584
Least number divisible by at least n of its digits, different and > 1.
1
2, 24, 248, 2364, 27384, 243768, 23469768, 1234759680
OFFSET
1,1
COMMENTS
a(1)=2=A185186(1), a(2)=24=A187516(1),
a(3)=248=A187398(1), a(4)=2364=A187238(1),
a(5)=27384=A187533(1), a(6)=243768=A187534(1),
a(7)=23469768=A187551(1), a(8)=1234759680=A187565(1).
MATHEMATICA
divQ[m_, n_] := Length[(u = Union[Select[IntegerDigits[m], # > 1 &]])] >= n && Plus @@ (Boole@Divisible[m, u]) >= n; a[n_] := Module[{k = 1}, While[! divQ[k, n], k++]; k]; Array[a, 8] (* Amiram Eldar, Aug 30 2020 *)
PROG
(Python)
def c(n): return len(set(d for d in str(n) if d>'1' and n%int(d)==0))
def a(n):
m = 2*10**(n-1)
while c(m) < n: m += 1
return m
print([a(n) for n in range(1, 7)]) # Michael S. Branicky, Feb 24 2021
KEYWORD
nonn,base,fini,full
AUTHOR
Zak Seidov, Mar 11 2011
EXTENSIONS
a(8) corrected by David A. Corneth, Aug 30 2020
STATUS
approved