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A131548
Least power of 3 having a run of exactly n consecutive 5's in its decimal representation.
9
8, 27, 33, 33, 274, 2076, 5173, 8880, 67390, 206131, 864271, 1291676, 5756979, 13654248, 73000220
OFFSET
1,1
EXAMPLE
a(3) = 33 because 3^33 = 5559060566555523 is the smallest power of 3 that contains a run of exactly 3 consecutive 5's in its decimal form. (3^33 happens to contain also a run of exactly 4 consecutive 5's, so a(4) is also 33.)
KEYWORD
more,nonn,base
AUTHOR
Shyam Sunder Gupta, Aug 26 2007
EXTENSIONS
a(11)-a(14) from Lars Blomberg, Feb 02 2013
a(15) from Bert Dobbelaere, Mar 05 2019
a(3) corrected by Pontus von Brömssen, Jul 21 2024
STATUS
approved