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A074153
Smallest n-digit power of n; or 0 if no such number exists.
1
1, 16, 243, 1024, 15625, 279936, 5764801, 16777216, 387420489, 1000000000, 25937424601, 743008370688, 1792160394037, 56693912375296, 129746337890625, 4503599627370496, 0, 374813367582081024, 0, 32768000000000000000, 0, 3011361496339065143296, 0
OFFSET
1,2
COMMENTS
Zeros become more common as n increases. - Sean A. Irvine, Jan 12 2025
FORMULA
For n >= 2, a(n) = ceiling((n-1)/log_10(n)), if ceiling((n-1)/log_10(n)) < ceiling(n/log_10(n)), and 0 otherwise. - Amiram Eldar, Jan 13 2025
MATHEMATICA
a[n_] := Module[{e1 = Ceiling[(n-1) * Log[n, 10]], e2 = Ceiling[n * Log[n, 10]]}, If[e1 == e2, 0, n^e1]]; a[1] = 1; Array[a, 23] (* Harvey P. Dale, Mar 04 2013, corrected by Amiram Eldar, Jan 13 2025 *)
CROSSREFS
Cf. A074154.
Sequence in context: A231020 A274856 A064232 * A119933 A274753 A207995
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy, Aug 29 2002
EXTENSIONS
More terms from Harvey P. Dale, Mar 04 2013
a(17) and a(19) corrected and more terms from Sean A. Irvine, Jan 12 2025
STATUS
approved