OFFSET
1,1
COMMENTS
"Unique [period] primes" (A040017) are often of the form Phi[k](10) or Phi[k](-10).
Two cyclotomic polynomial identities tightly connect this sequence to A138940: 1) Phi_2k(x) = Phi_k(-x) for odd integer k > 1. 2) Phi_4k(x) = Phi_2k(x^2) for all positive integer k. - Ray Chandler, Apr 30 2017
LINKS
Ray Chandler, Table of n, a(n) for n = 1..89 (first 76 terms from Robert Price)
C. Caldwell, Unique Primes.
MATHEMATICA
Select[Range[1000], PrimeQ[Cyclotomic[#, -10]] &]
PROG
(PARI) for( i=1, 999, is/*pseudo*/prime( polcyclo(i, -10)) &&& print1( i", ")) /* for PARI < 2.4.2 use ...subst(polcyclo(i, x), x, -10)... */
CROSSREFS
KEYWORD
nonn
AUTHOR
M. F. Hasler, Apr 03 2008
EXTENSIONS
a(28)-a(43) from Robert Price, Mar 09 2012
a(44)-a(50) from Robert Price, Apr 14 2012
STATUS
approved