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A256575
Nonsquarefree orders of cyclotomic polynomials containing a coefficient with an absolute value greater than one.
0
315, 420, 495, 525, 585, 630, 660, 735, 765, 780, 819, 825, 840, 855, 945, 975, 990, 1020, 1035, 1050, 1071, 1092, 1140, 1170, 1260, 1275, 1287, 1320, 1380, 1425, 1428, 1470, 1485, 1530, 1540, 1560, 1575, 1638, 1650, 1665, 1680, 1683, 1710, 1716, 1725, 1755, 1815, 1820, 1827, 1845, 1881, 1890, 1911, 1925
OFFSET
1,1
COMMENTS
Numbers in A013590 that are not squarefree.
PROG
(PARI) is(n)=if (!issquarefree(n), for(k=0, n, if(abs(polcoeff(polcyclo(n), k))>1, return(n))); 0)
for(n=1, 10^4, if(is(n), print1(n, ", "))) \\ edited by Michel Marcus, Apr 21 2018
CROSSREFS
Sequence in context: A210891 A076648 A323380 * A295990 A349868 A349937
KEYWORD
nonn
AUTHOR
Derek Orr, Apr 22 2015
STATUS
approved