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A068121 Smallest n-th power beginning with the concatenation of first n natural numbers. 3
1, 121, 12326391, 1234134359056, 1234543668832, 1234566439851412003312246012968681, 123456718029050407240974433459138845096817901 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
B-file stops at a(25) because a(26) has 1107 digits. - Giovanni Resta, Jul 12 2016
LINKS
EXAMPLE
12326391 = 231^3 is the smallest cube beginning with 123.
MATHEMATICA
a[n_] := Block[{t = Flatten@ Table[ IntegerDigits@i, {i, n}], m, v, h = 0}, m = Length@t; z = FromDigits@t; While[ Take[ IntegerDigits[(v = Ceiling[(z 10^h) ^ (1/n)])^n], m] != t, h++]; v^n]; Array[a, 25] (* Giovanni Resta, Jul 12 2016 *)
CROSSREFS
Cf. A068122.
Sequence in context: A053885 A068490 A077735 * A013859 A303897 A060032
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy, Feb 21 2002
EXTENSIONS
More terms from Robert Gerbicz, Sep 05 2002
Edited by N. J. A. Sloane at the suggestion of Andrew S. Plewe, Jun 15 2007
STATUS
approved

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Last modified March 18 22:56 EDT 2024. Contains 370952 sequences. (Running on oeis4.)