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A071565
Numbers k such that x^k + x^(k-1) + x^(k-2) + ... + x + 1 is irreducible over GF(7).
0
4, 10, 12, 16, 22, 40, 60, 66, 70, 78, 88, 96, 100, 106, 126, 150, 162, 172, 178, 210, 228, 238, 240, 256, 262, 268, 292, 346, 348, 358, 378, 396, 430, 432, 442, 460, 490, 498, 508, 520, 546, 576, 592, 598, 600, 630, 658, 676, 682, 732, 738, 742, 760, 772
OFFSET
1,1
FORMULA
a(n) = A019337(n+1) - 1. - Joerg Arndt, Apr 17 2020
CROSSREFS
Cf. A071642.
Cf. A019337. - Joerg Arndt, Apr 17 2020
Sequence in context: A117099 A026180 A109274 * A233741 A310340 A285570
KEYWORD
easy,nonn
AUTHOR
Robert G. Wilson v, Jun 22 2002
STATUS
approved