A318884 a(n) is the sum of absolute values of the coefficients in the n-th cyclotomic polynomial.

2, 2, 3, 2, 5, 3, 7, 2, 3, 5, 11, 3, 13, 7, 7, 2, 17, 3, 19, 5, 9, 11, 23, 3, 5, 13, 3, 7, 29, 7, 31, 2, 15, 17, 17, 3, 37, 19, 17, 5, 41, 9, 43, 11, 7, 23, 47, 3, 7, 5, 23, 13, 53, 3, 17, 7, 25, 29, 59, 7, 61, 31, 9, 2, 31, 15, 67, 17, 31, 17, 71, 3, 73, 37, 7, 19, 31, 17, 79, 5, 3, 41, 83, 9, 41, 43, 39, 11, 89

Offset

1,1

Comments

Differs from A051664 in the positions given by A013590, thus for the first time at n=105, where a(105) = 35, while A051664(105) = 33 as the 105th cyclotomic polynomial is the first one that has a coefficient other than 1, 0, or -1.

Links

Antti Karttunen, Table of n, a(n) for n = 1..65537

Eric Weisstein's World of Mathematics, Cyclotomic Polynomial

Wikipedia, Cyclotomic polynomial

Mathematica

Array[Total@ Abs@ CoefficientList[Cyclotomic[#, x], x] &, 89] (* Michael De Vlieger, Sep 10 2018 *)

Prog

(PARI) A318884(n) = vecsum(apply(abs, Vec(polcyclo(n)))); \\ Antti Karttunen, Sep 10 2018

Crossrefs

Cf. A013590, A013595, A051258, A051664, A318886.

Sequence in context: A238480 A111089 A051664 * A280990 A327667 A256267

Adjacent sequences: A318881 A318882 A318883 * A318885 A318886 A318887

Keyword

nonn

Author

Antti Karttunen, Sep 10 2018

Status

approved