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A087482
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Number of binary polynomials of degree n irreducible over the integers.
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2
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2, 2, 2, 6, 8, 21, 34, 84, 150, 331, 614, 1417, 2638, 5508, 10874, 23437
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| A binary polynomial is defined as a monic polynomial whose remaining coefficients are either 0 or 1. For each n, there are 2^n polynomials to consider.
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LINKS
| Eric Weisstein's World of Mathematics, Irreducible Polynomial
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MATHEMATICA
| Irreducible[p_, n_] := Module[{f}, f=FactorList[p, Modulus->n]; Length[f]==1 || Simplify[p-f[[2, 1]]]===0]; Table[xx=x^Range[0, n-1]; cnt=0; Do[p=x^n+xx.(IntegerDigits[i, 2, n]); If[Irreducible[p, 0], cnt++ ], {i, 0, 2^n-1}]; cnt, {n, 16}]
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CROSSREFS
| Cf. A087481 (irreducible polynomials of the form x^n +- x^(n-1) +- x^(n-2) +- ... +- 1).
Sequence in context: A194676 A151694 A121698 * A137227 A052537 A024945
Adjacent sequences: A087479 A087480 A087481 * A087483 A087484 A087485
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KEYWORD
| nonn
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AUTHOR
| T. D. Noe (noe(AT)sspectra.com), Sep 09 2003
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