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A030673
Smallest cube that begins with n-th prime.
2
27, 343, 512, 729, 110592, 1331, 1728, 19683, 238328, 29791, 314432, 373248, 4173281, 438976, 474552, 531441, 59319, 614125, 6751269, 7189057, 7301384, 79507, 830584, 8998912, 97336, 101194696, 103823, 10793861, 1092727, 11390625
OFFSET
1,1
LINKS
FORMULA
a(n) = A018797(A000040(n)).
EXAMPLE
a(1) = 27 because 27 = 3^3 is the smallest cube beginning (base 10) with prime(1) = 2.
a(2) = 343 because 343 = 7^3 is the smallest cube beginning (base 10) with prime(2) = 3.
MATHEMATICA
f[n_] := Block[{k, l = Ceiling@ Log[10, Prime@ n], p = IntegerDigits@ Prime@ n}, k = Ceiling[ Prime[n]^(1/3)]; While[ Take[ IntegerDigits[k^3], l] != p, k++ ]; k^3]; Array[f, 31] (* Robert G. Wilson v, May 31 2008 *)
CROSSREFS
KEYWORD
base,easy,nonn
EXTENSIONS
Edited by N. J. A. Sloane, Aug 29 2008 at the suggestion of R. J. Mathar
STATUS
approved