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A091220 Number of divisors of the n-th GF(2)[X]-polynomial. 10
1, 2, 2, 3, 3, 4, 2, 4, 4, 6, 2, 6, 2, 4, 4, 5, 5, 8, 2, 9, 3, 4, 4, 8, 2, 4, 6, 6, 4, 8, 2, 6, 4, 10, 4, 12, 2, 4, 6, 12, 2, 6, 4, 6, 8, 8, 2, 10, 4, 4, 6, 6, 4, 12, 2, 8, 6, 8, 2, 12, 2, 4, 6, 7, 9, 8, 2, 15, 3, 8, 4, 16, 2, 4, 8, 6, 4, 12, 4, 15, 3, 4, 8, 9, 7, 8, 2, 8, 4, 16, 2, 12, 4, 4, 6, 12, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..97.

A. Karttunen, Scheme-program for computing this sequence.

Index entries for sequences operating on GF(2)[X]-polynomials

PROG

(PARI) a(n)=local(p, fm, k); while(n>0, p+=Mod(n, 2)*x^k; n\=2; k++); fm=factor(p); prod(k=1, matsize(fm)[1], fm[k, 2]+1) \\ Franklin T. Adams-Watters, Jun 22 2010

CROSSREFS

a(n) = A000005(A091203(n)) = A000005(A091205(n)). Cf. A091257.

Sequence in context: A106494 A015135 A116619 * A057955 A305788 A116473

Adjacent sequences:  A091217 A091218 A091219 * A091221 A091222 A091223

KEYWORD

nonn

AUTHOR

Antti Karttunen, Jan 03 2004

STATUS

approved

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Last modified October 20 15:22 EDT 2018. Contains 316388 sequences. (Running on oeis4.)