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A250195 Numbers n such that Phi(49,n) is prime, where Phi is the cyclotomic polynomial. 2
1, 2, 5, 62, 67, 104, 123, 138, 151, 186, 194, 233, 236, 261, 269, 306, 359, 416, 425, 439, 557, 613, 695, 705, 742, 748, 821, 832, 884, 885, 892, 902, 936, 937, 1125, 1165, 1176, 1248, 1265, 1320, 1337, 1386, 1544, 1594, 1675, 1707, 1712, 1714, 1722, 1725, 1798, 1840, 1844 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

G. C. Greubel, Table of n, a(n) for n = 1..10000

MATHEMATICA

Select[Range[1900], PrimeQ[Cyclotomic[49, #]] &] (* Vincenzo Librandi, Jan 17 2015 *)

PROG

(PARI) {is(n)=isprime(polcyclo(49, n))};

for(n=1, 1000, if(is(n), print1(n, ", "))) \\ G. C. Greubel, May 20 2018

CROSSREFS

Cf. A246392.

Sequence in context: A062642 A294528 A093484 * A041069 A217053 A134590

Adjacent sequences:  A250192 A250193 A250194 * A250196 A250197 A250198

KEYWORD

nonn

AUTHOR

R. J. Mathar, Jan 12 2015

STATUS

approved

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Last modified September 22 02:48 EDT 2021. Contains 347605 sequences. (Running on oeis4.)