A154430 Odd squarefree numbers n such that the cyclotomic polynomial Phi(n,x) has height > 1.

105, 165, 195, 255, 273, 285, 345, 357, 385, 429, 455, 555, 561, 595, 609, 615, 627, 645, 665, 705, 715, 759, 777, 795, 805, 897, 935, 957, 969, 987, 1001, 1005, 1015, 1023, 1045, 1065, 1085, 1095, 1105, 1131, 1155, 1185, 1221, 1235, 1239, 1245, 1265

Offset: 1

Author

T. D. Noe, Jan 09 2009

Keywords

• nonn

Comments

The height of a polynomial is the maximum of the absolute value of its coefficients. Different from A118678, which excludes terms that are a multiple of smaller terms.

Links

• T. D. Noe, Table of n, a(n) for n = 1..1000

Crossrefs

Cf. A013590, A117318, A117223, A152940, A152941, A152942, A152943, A152955.

Programs

Mathematica

Select[Range[2000], OddQ[#] && SquareFreeQ[#] && Max[ Abs[ CoefficientList[ Cyclotomic[#, x], x]]] > 1&] (* Jean-François Alcover, Nov 14 2016 *)

PARI

is(n)=issquarefree(n) && n%2 && vecmax(abs(Vec(polcyclo(n))))>1 \\ Charles R Greathouse IV, Nov 05 2017