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A053725
Number of n X n binary matrices of order dividing 3 (also number of solutions to X^3=I in GL(n,2)).
30
1, 3, 57, 1233, 75393, 19109889, 6326835201, 6388287561729, 23576681450405889, 120906321631678693377, 1968421511613895105052673, 111055505036706392268074909697, 8965464105556083354144035638870017
OFFSET
1,2
REFERENCES
V. Jovovic, The cycle index polynomials of some classical groups, Belgrade, 1995, unpublished.
LINKS
Kent E. Morrison, Integer Sequences and Matrices Over Finite Fields, Journal of Integer Sequences, Vol. 9 (2006), Article 06.2.1.
PROG
(PARI) \\ See Morison theorem 2.6
\\ F(n, q, k) is number of solutions to X^k=I in GL(i, GF(q)) for i=1..n.
\\ q is power of prime and gcd(q, k) = 1.
B(n, q, e)={sum(m=0, n\e, x^(m*e)/prod(k=0, m-1, q^(m*e)-q^(k*e)))}
F(n, q, k)={if(gcd(q, k)<>1, error("no can do")); my(D=ffgen(q)^0); my(f=factor(D*(x^k-1))); my(p=prod(i=1, #f~, (B(n, q, poldegree(f[i, 1])) + O(x*x^n))^f[i, 2])); my(r=B(n, q, 1)); vector(n, i, polcoeff(p, i)/polcoeff(r, i))}
F(10, 2, 3) \\ Andrew Howroyd, Jul 09 2018
KEYWORD
nonn
AUTHOR
Vladeta Jovovic, Mar 23 2000
STATUS
approved