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A068122
Smallest number whose n-th power begins with concatenation of first n numbers; n-th root of A068121.
3
1, 11, 231, 1054, 262, 327531, 1989701, 43295162, 367895001, 51186035996, 1019341118828, 180978193207225, 24640811037579724, 861208311784429084, 470725434700902227811, 15603415956731968190389, 2613051323334500973960814
OFFSET
1,2
LINKS
EXAMPLE
a(3) = 231 as 231^3=12326391 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]; Array[a, 30] (* Giovanni Resta, Jul 12 2016 *)
CROSSREFS
Cf. A068121.
Sequence in context: A108518 A346423 A077736 * A015287 A254782 A169960
KEYWORD
base,easy,nonn
AUTHOR
Amarnath Murthy, Feb 21 2002
EXTENSIONS
More terms from Robert Gerbicz, Sep 05 2002
STATUS
approved