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A325870 Primes represented by non quadratic cyclotomic binary forms. 1
11, 13, 17, 31, 43, 61, 73, 97, 127, 151, 181, 193, 211, 241, 257, 331, 337, 421, 461, 463, 521, 541, 547, 577, 601, 641, 683, 757, 881, 991, 1009, 1021, 1031, 1093, 1297, 1621, 1801, 1871, 1873, 1933, 2221, 2417, 2657, 2731, 2801, 3001, 3121, 3361, 3571, 3697 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Peter Luschny, Table of n, a(n) for n = 1..185

Etienne Fouvry, Claude Levesque, Michel Waldschmidt, Representation of integers by cyclotomic binary forms, arXiv:1712.09019 [math.NT], 2017 and Acta Arithmetica, online 15 March 2018.

PROG

(PARI)

isA325870(n) =

{

    my(K, M, phi);

    K = floor(5.383*log(n)^1.161);

    M = floor(2*sqrt(n/3));

    for(k = 3, K,

        phi = eulerphi(k);

        if(phi >= 4,

            for(y = 1, M,

                for(x = y + 1, M,

                    if(n == y^phi*polcyclo(k, x/y),

                        return(1)

    )))));

    return(0)

}

CROSSREFS

Cf. A296095, A293654, A325143, A325145.

Sequence in context: A185104 A240570 A162237 * A090236 A240623 A240624

Adjacent sequences:  A325867 A325868 A325869 * A325871 A325872 A325873

KEYWORD

nonn

AUTHOR

Peter Luschny, May 26 2019

EXTENSIONS

At the suggestion of Michel Waldschmidt.

STATUS

approved

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Last modified August 14 09:14 EDT 2020. Contains 336480 sequences. (Running on oeis4.)