OFFSET
1,1
COMMENTS
The exponents are given in A066343. - Evgeny Kapun, Jan 16 2017
An equivalent definition (which was formerly the definition of A074113): "Smallest n-digit number of the form p^a*q^b... with the maximum value of a+b+.... where p, q etc. are primes. If a,b,c,... are the indices in the signature prime factorization then a+b+c ... is a maximum." That this is the same sequence follows from the inequality p^a*q^b... >= 2^(a+b+...) and the fact that there always exists a power of 2 between two consecutive powers of 10.
LINKS
Evgeny Kapun, Table of n, a(n) for n = 1..1000
FORMULA
a(n) = 2^A066343(n). - Evgeny Kapun, Jan 16 2017
MATHEMATICA
Last[#]&/@(With[{l2=2^Range[80]}, Table[Select[l2, IntegerLength[#] == n&], {n, 22}]]) (* Harvey P. Dale, Jul 17 2011 *)
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy, Aug 27 2002
EXTENSIONS
Edited by R. J. Mathar, Feb 13 2008, Max Alekseyev, Mar 10 2009, Harvey P. Dale, Jul 17 2011, Evgeny Kapun, Jan 16 2017, and N. J. A. Sloane, Jan 18 2017
STATUS
approved