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 A013590 Numbers k such that Phi(k,x) is a cyclotomic polynomial containing a coefficient with an absolute value greater than one. 9
 105, 165, 195, 210, 255, 273, 285, 315, 330, 345, 357, 385, 390, 420, 429, 455, 495, 510, 525, 546, 555, 561, 570, 585, 595, 609, 615, 627, 630, 645, 660, 665, 690, 705, 714, 715, 735, 759, 765, 770, 777, 780, 795, 805, 819, 825, 840, 855 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Previous name was: Orders of cyclotomic polynomials containing a coefficient with an absolute value greater than one. First occurrence of A137979(n)=k is given in A013594. From David A. Corneth, Apr 21 2018: (Start) Terms are composite. If k is a term of the sequence then so is k * m for m > 0. Let a primitive term p of this sequence be a term of which no divisor is in the sequence. Then p is an odd squarefree number. (End) LINKS Robert G. Wilson v, Table of n, a(n) for n = 1..1627 MAPLE isA013590 := proc(n)     numtheory[cyclotomic](n, x) ;     {coeffs(%, x)} ;     map(abs, %) ;     if % minus {1}  = {} then         false;     else         true;     end if; end proc: for n from 1 do     if isA013590(n) then         print(n);     end if; end do: # R. J. Mathar, Nov 28 2016 MATHEMATICA S[ n_ ] := For[ j=1; t=0, j1 ]; If[ Length[ t ]!=0, Print[ j ] ] ]; S[ 856 ] f[n_] := Max@ Abs@ CoefficientList[ Cyclotomic[n, x], x]; Select[ Range@ 1000, f@# > 1 &] (* Robert G. Wilson v *) Select[Range, Max[Abs[CoefficientList[Cyclotomic[#, x], x]]]>1&] (* Harvey P. Dale, Mar 13 2013 *) PROG (PARI) is(n)=for(k=0, n, if(abs(polcoeff(polcyclo(n), k))>1, return(n))); 0 for(n=1, 1000, if(is(n), print1(n, ", "))) \\ Derek Orr, Apr 22 2015 CROSSREFS Cf. A013594, A117223, A117318, A137979. Flat cyclotomic polynomial: A117223 (order 3), A117318 (order 4). Sequence in context: A203614 A252069 A133509 * A216918 A278569 A046389 Adjacent sequences:  A013587 A013588 A013589 * A013591 A013592 A013593 KEYWORD nonn AUTHOR Peter T. Wang (peterw(AT)cco.caltech.edu) EXTENSIONS Definition clarified by Harvey P. Dale, Mar 13 2013 New name from Michel Marcus, Apr 29 2018 STATUS approved

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Last modified November 12 22:16 EST 2019. Contains 329079 sequences. (Running on oeis4.)