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A172469
Primes congruent to +/-1 or +/-7 modulo 25.
1
7, 43, 101, 107, 149, 151, 157, 193, 199, 251, 257, 293, 307, 349, 401, 443, 449, 457, 499, 557, 593, 599, 601, 607, 643, 701, 743, 751, 757, 857, 907, 1049, 1051, 1093, 1151, 1193, 1201, 1249, 1301, 1307, 1399, 1451, 1493, 1499, 1543, 1549, 1601, 1607
OFFSET
1,1
COMMENTS
Equivalently, primes p such that the smallest extension of F_p containing the 5th roots of unity also contains the 25th roots of unity.
In this respect, the sequence is the n=5 instance of a family of sequences. For n=3, see A129805, and for n=2, see A002144.
Equivalently, the primes p for which, if p^t = 1 mod 5, then p^t = 1 mod 25.
FORMULA
A141927 U A141932 U A141946 U A141941. [From R. J. Mathar, Feb 05 2010]
CROSSREFS
Sequence in context: A297306 A247949 A031914 * A216301 A201717 A134154
KEYWORD
easy,nonn
AUTHOR
Katherine E. Stange, Feb 03 2010
EXTENSIONS
More terms from R. J. Mathar, Feb 05 2010
STATUS
approved