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A095253
a(n) = floor(concatenation(n,(n-1),...,3,2,1)^(1/n)).
1
1, 4, 6, 8, 8, 9, 9, 9, 9, 10, 12, 14, 17, 19, 22, 24, 26, 28, 30, 32, 34, 36, 38, 39, 41, 42, 44, 45, 46, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 59, 60, 61, 61, 62, 63, 63, 64, 65, 65, 66, 66, 67, 67, 68, 68, 69, 69, 70, 70, 71, 71, 71, 72, 72, 72
OFFSET
1,2
EXAMPLE
a(4) = floor(4321^(1/4)) = 8.
MATHEMATICA
Table[Floor[Surd[FromDigits[Flatten[IntegerDigits/@Range[n, 1, -1]]], n]], {n, 80}] (* Harvey P. Dale, Apr 21 2014 *)
PROG
(PARI) a(n) = {my(t=n); forstep(k=n-1, 1, -1, t=t*10^#Str(k)+k); sqrtnint(t, n); } \\ Jinyuan Wang, Mar 22 2020
CROSSREFS
Sequence in context: A372790 A163639 A196355 * A027709 A196358 A079775
KEYWORD
nonn,base
AUTHOR
Amarnath Murthy, Jun 17 2004
EXTENSIONS
More terms from Harvey P. Dale, Apr 21 2014
STATUS
approved