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A174229 Natural numbers n such that the concatenation n^3//1331, i.e., a cube and 11^3, is a prime number. 1
2, 6, 8, 14, 21, 38, 39, 51, 54, 65, 68, 78, 80, 93, 104, 107, 114, 117, 119, 125, 135, 137, 146, 147, 152, 153, 158, 159, 167, 186, 206, 225, 243, 246, 248, 257, 258, 269, 270, 272, 278, 284, 290, 291, 306, 311, 317, 321, 323, 324, 369, 372, 387, 390, 399, 404, 410, 414, 425 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

See comments and references for A174213.

LINKS

Table of n, a(n) for n=1..59.

EXAMPLE

2^3 = 8, 81331 = prime(7958) => a(1) = 2;

6^3 = 216, 2161331 = prime(160048) => a(2) = 6.

PROG

(PARI) isok(n) = isprime(eval(concat(Str(n^3), Str(1331)))); \\ Michel Marcus, Jul 20 2017

CROSSREFS

Cf. A168327, A168417, A173836, A174213.

Sequence in context: A270050 A137831 A117588 * A187217 A022112 A107019

Adjacent sequences:  A174226 A174227 A174228 * A174230 A174231 A174232

KEYWORD

base,nonn

AUTHOR

Eva-Maria Zschorn (e-m.zschorn(AT)zaschendorf.km3.de), Mar 13 2010

EXTENSIONS

More terms from Michel Marcus, Jul 20 2017

STATUS

approved

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Last modified April 13 17:30 EDT 2021. Contains 342936 sequences. (Running on oeis4.)