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1,1
Conjecture:
Lim_n->inf. of a(2n)/10^n=1-1/sqrt(10) and
Lim_n->inf. of a(2n-1)/10^n=1/sqrt(10)-1/10. Robert G. Wilson v, Aug 29 2012
Table of n, a(n) for n=1..27.
a(1) = 3 because there are 3 powers with 1 digit: 2^2, 2^3 and 3^2.
Sequence in context: A081423 A184705 A257890 * A226546 A073372 A026573
Adjacent sequences: A060295 A060296 A060297 * A060299 A060300 A060301
nonn,base
Michel ten Voorde (seqfan(AT)tenvoorde.org) Apr 10 2001
a(10)-a(18) from Donovan Johnson, Dec 14 2009
a(19)-a(27) from Donovan Johnson, Aug 29 2012
approved