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A138940 Indices n such that A019328(n)=Phi[n](10) is prime, where Phi is a cyclotomic polynomial. +0
20
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; listen)
OFFSET

1,1

COMMENT

"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

PROGRAM

(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: A136818 A029984 A101519 this_sequence A129412 A113536 A081887

Adjacent sequences: A138937 A138938 A138939 this_sequence A138941 A138942 A138943

KEYWORD

nonn,more

AUTHOR

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

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Last modified November 24 23:16 EST 2009. Contains 167481 sequences.


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