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A362675
Smallest number sharing n distinct (decimal) digits with its largest proper divisor.
0
11, 125, 1025, 3105, 37125, 251748, 2051748, 20491578, 204713568, 2046913578
OFFSET
1,1
EXAMPLE
------------------------------------------------
n a(n) Largest proper divisor of a(n)
------------------------------------------------
1 11 1
2 125 25
3 1025 205
4 3105 1035
5 37125 12375
6 251748 125874
7 2051748 1025874
8 20491578 10245789
9 204713568 102356784
10 2046913578 1023456789
PROG
(PARI) f(n) = n/factor(n)[1, 1]; \\ A032742
a(n) = my(k=2); while (#setintersect(Set(digits(k)), Set(digits(f(k)))) != n, k++); k; \\ Michel Marcus, Apr 29 2023
(Python)
from sympy import factorint
from itertools import count
def a(n):
lb = 2*int("1023456789"[:n])
return next(k for k in count(lb) if len(set(str(k)) & set(str(k//min(factorint(k))))) == n)
print([a(n) for n in range(1, 11)]) # Michael S. Branicky, Apr 29 2023
CROSSREFS
KEYWORD
nonn,fini,full,base
AUTHOR
Wesley Ivan Hurt, Apr 29 2023
EXTENSIONS
a(9) from Michel Marcus, Apr 29 2023
a(10) from Michael S. Branicky, Apr 29 2023
STATUS
approved