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A090900
Least n-th power such that every concatenation is a prime.
1
2, 9, 27, 6561, 39135393, 1291467969, 3404825447, 248155780267521, 8422942255954625293713, 717897987691852588770249
OFFSET
1,1
EXAMPLE
2, 29, 2927, etc. are primes.
MATHEMATICA
c = ""; Do[k = 1; While[ !PrimeQ[ToExpression[c <> ToString[k^n]]], k++ ]; Print[k^n]; c = c <> ToString[k^n], {n, 1, 10}] (* Ryan Propper, Jul 08 2005 *)
CROSSREFS
Sequence in context: A019065 A115186 A243560 * A357721 A155472 A100293
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy, Dec 11 2003
EXTENSIONS
More terms from Ryan Propper, Jul 08 2005
STATUS
approved