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A152940 Odd squarefree numbers n such that the cyclotomic polynomial Phi(n,x) has height 2. 7
105, 165, 195, 255, 273, 285, 345, 357, 429, 455, 555, 561, 609, 615, 627, 645, 705, 715, 759, 777, 795, 805, 897, 957, 969, 987, 1001, 1005, 1015, 1023, 1045, 1065, 1085, 1095, 1105, 1131, 1185, 1221, 1239, 1245, 1265, 1295, 1407, 1419, 1435, 1455, 1491 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The height of a polynomial is the maximum of the absolute value of its coefficients. Subsequence of A154430.

LINKS

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

PROG

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

CROSSREFS

Cf. A152955, A152941, A152942, A152943.

Sequence in context: A046389 A154430 A118678 * A189936 A076762 A036798

Adjacent sequences:  A152937 A152938 A152939 * A152941 A152942 A152943

KEYWORD

nonn

AUTHOR

T. D. Noe, Dec 16 2008, Jan 09 2009

STATUS

approved

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Last modified October 15 01:40 EDT 2019. Contains 328025 sequences. (Running on oeis4.)