

A117318


Numbers n such that Phi(n,x) is a flat cyclotomic polynomial of order four.


7



431985, 757335, 865365, 1134915, 1296885, 1297815, 1675365, 1729335, 1891815, 2161785, 2162715, 2595165, 2648715, 2649585, 3027165, 3028035, 3132015, 3133785, 3347985, 3405615, 3565785, 3784065, 3891585, 4698465, 4920285, 5188935, 5189865, 5676315
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OFFSET

1,1


COMMENTS

A flat polynomial is defined to be a polynomial whose coefficients are 1, 0, or 1. Order four means that n is the product of four odd primes p<q<r<s.
For pqrs to be flat, it appears that three conditions on p < q < r < s are required: q = 1 (mod p), r = +1 (mod pq), and s = +1 (mod pqr). [T. D. Noe, Apr 13 2010]


LINKS

T. D. Noe, Table of n, a(n) for n=1..216
Nathan Kaplan, Flat cyclotomic polynomials of order four and higher, #A30, Integers 10 (2010), 357363.


CROSSREFS

Cf. A117223 (thirdorder flat cyclotomic polynomials).
Sequence in context: A233620 A271110 A237926 * A085092 A117151 A186048
Adjacent sequences: A117315 A117316 A117317 * A117319 A117320 A117321


KEYWORD

nonn


AUTHOR

T. D. Noe, Mar 07 2006


STATUS

approved



