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A305941
Smallest power of n having at least one digit 0 (when written in base 10).
2
1024, 59049, 1024, 390625, 10077696, 2401, 4096, 59049, 10, 161051, 20736, 4826809, 105413504, 50625, 4096, 410338673, 104976, 130321, 20, 4084101, 10648, 148035889, 191102976, 390625, 308915776, 14348907, 17210368, 707281, 30, 887503681, 1024, 1089, 39304, 1500625, 60466176, 50653, 2085136, 90224199, 40
OFFSET
2,1
COMMENTS
One would have a(0) = 0 (= 0^1), but a(1) is undefined.
The similar sequence defined as "...exactly one digit 0..." would be ill-defined for all powers of 100, 1001, and others.
FORMULA
a(n) >= n, with equality iff n is in A011540 \ {0} = {10, 20, ..., 100, 101, ...}.
PROG
(PARI) apply( A305941(n)=for(k=1, oo, vecmin(digits(n^k))||return(n^k)), [2..20])
CROSSREFS
Cf. A071531.
Sequence in context: A321834 A182681 A182682 * A351198 A195250 A016901
KEYWORD
nonn,easy,base
AUTHOR
M. F. Hasler, Jun 19 2018
STATUS
approved