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A168487
Primes of the form 100n^3 + 27.
1
127, 827, 6427, 12527, 34327, 219727, 491327, 1562527, 2438927, 3276827, 8518427, 16637527, 22698127, 43897627, 45653327, 51200027, 77868827, 119101627, 129502927, 140492827, 156089627, 177156127, 190662427, 251545627, 257135327
OFFSET
1,1
COMMENTS
(1) These primes all with the end digits 2 and 7 are concatenations of two CUBIC numbers: "n^3 3^3".
(2) It is conjectured that sequence is infinite.
REFERENCES
Harold Davenport, Multiplicative Number Theory, Springer-Verlag New-York 1980
Leonard E. Dickson: History of the Theory of numbers, vol. I, Dover Publications 2005
Friedhelm Padberg, Elementare Zahlentheorie, Spektrum Akademischer Verlag, 2. Auflage 1991
MATHEMATICA
Select[100Range[140]^3+27, PrimeQ] (* Harvey P. Dale, Aug 22 2011 *)
CROSSREFS
A167535 Concatenation of two square numbers which give a prime
A168147 Primes of the form p = 1 + 10*n^3 for a natural number n
A168327 Primes of concatenated form p = "1 n^3"
Sequence in context: A060201 A140630 A183829 * A299057 A299818 A236304
KEYWORD
nonn
AUTHOR
Eva-Maria Zschorn (e-m.zschorn(AT)zaschendorf.km3.de), Nov 27 2009
EXTENSIONS
Edited by Charles R Greathouse IV, Apr 24 2010
STATUS
approved