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A138940 Indices n such that A019328(n)=Phi[n](10) is prime, where Phi is a cyclotomic polynomial. 19
2, 4, 10, 12, 14, 19, 23, 24, 36, 38, 39, 48, 62, 93, 106, 120, 134, 150, 196, 317, 320, 385, 586, 597, 654, 738, 945 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

"Unique [period] primes" (A040017) are often of the form Phi[k](10) or Phi[k](-10).

LINKS

C. Caldwell, Unique Primes.

Index entries for cyclotomic polynomials, values at X

PROG

(PARI) for( i=1, 999, isprime( polcyclo(i, 10)) && print1( i", ")) /* for PARI < 2.4.2 use ...subst(polcyclo(i, x), x, 10)... */

CROSSREFS

Cf. A019328, A040017.

Sequence in context: A029984 A101519 A184815 * A129412 A113536 A081887

Adjacent sequences:  A138937 A138938 A138939 * A138941 A138942 A138943

KEYWORD

nonn,more

AUTHOR

M. F. Hasler (www.univ-ag.fr/~mhasler), Apr 03 2008

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Last modified February 14 23:53 EST 2012. Contains 205689 sequences.