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A110097 Numbers n such that the string 444n is prime. 0
1, 7, 17, 49, 53, 83, 91, 97, 109, 113, 121, 127, 131, 151, 167, 173, 179, 181, 187, 209, 253, 271, 281, 287, 289, 293, 307, 341, 343, 347, 349, 401, 403, 421, 443, 449, 461, 463, 469, 473, 487, 517, 523, 527, 529, 539, 547, 553, 557, 569, 589, 607, 623, 637 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..54.

EXAMPLE

If n=113 then 444n = 444113 (prime).

MATHEMATICA

Select[Range[1000], PrimeQ[FromDigits[Join[{4, 4, 4}, IntegerDigits[#]]]]&] (* Harvey P. Dale, Dec 02 2010 *)

CROSSREFS

Sequence in context: A195905 A104164 A192244 * A179262 A018672 A221591

Adjacent sequences:  A110094 A110095 A110096 * A110098 A110099 A110100

KEYWORD

nonn,base

AUTHOR

Parthasarathy Nambi, Sep 05 2005

EXTENSIONS

More terms from Vincenzo Librandi, Mar 27 2010

STATUS

approved

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Last modified December 12 22:06 EST 2019. Contains 329963 sequences. (Running on oeis4.)