OFFSET
1,1
LINKS
Michael S. Branicky, Table of n, a(n) for n = 1..10000
FORMULA
a(n) <= 10^A055642(n). - Michael S. Branicky, Jan 29 2024
EXAMPLE
a(12) = 26 because 26 is the smallest integer greater than 12 such that 12 * 26 = 312 contains 12 as a substring.
MATHEMATICA
a[n_]:=(k=n+1; While[!StringContainsQ[ToString[n*k], ToString@n], k++]; k); Array[a, 70]
PROG
(Python)
from itertools import count
def a(n):
s = str(n)
return next(k for k in count(n+1) if s in str(k*n))
print([a(n) for n in range(1, 71)]) # Michael S. Branicky, Jan 29 2024
CROSSREFS
KEYWORD
AUTHOR
Giorgos Kalogeropoulos, Jan 29 2024
STATUS
approved