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A059913 Triangle T(n,k) of numbers of n degree irreducible polynomials over GF(2) which have order A059912(n,k), k=1..A059499(n). 2
2, 1, 2, 1, 2, 6, 1, 2, 6, 18, 2, 4, 8, 16, 8, 48, 1, 2, 6, 30, 60, 2, 8, 176, 1, 2, 2, 2, 4, 6, 4, 6, 8, 12, 12, 24, 24, 36, 48, 144, 630, 3, 6, 18, 378, 756, 10, 12, 60, 300, 1800, 16, 32, 64, 128, 256, 512, 1024, 2048, 7710, 1, 1, 2, 6, 6, 6, 8, 12, 18, 24 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row sums give A001037.

LINKS

Alois P. Heinz, Rows n = 1..71, flattened

FORMULA

T(n,k) = phi(A059912(n,k))/n, where phi = Euler totient function A000010.

EXAMPLE

Triangle T(n,k) begins:

2;

1;

2;

1,  2;

6;

1,  2,   6;

18;

2,  4,   8, 16;

8, 48;

1,  2,   6, 30, 60;

2,  8, 176;

There are 9 (cf. A001037) irreducible polynomials of degree 6 over GF(2): 1 of order 9, 2 of order 21 and 6 of order 63 (cf. A059912).

CROSSREFS

Cf. A058943, A059478, A059499, A001037, A059912, A059914-A059916, A000010.

Sequence in context: A020733 A210700 A215745 * A083273 A193163 A106157

Adjacent sequences:  A059910 A059911 A059912 * A059914 A059915 A059916

KEYWORD

easy,nonn,tabf

AUTHOR

Vladeta Jovovic, Feb 09 2001

STATUS

approved

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Last modified March 19 17:21 EDT 2019. Contains 321330 sequences. (Running on oeis4.)