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A053293 revision #28

A053293
Number of nonsingular n X n matrices over GF(7).
14
1, 6, 2016, 33784128, 27811094169600, 1122211189922928537600, 2218959336124989671614429593600, 214992513152176999576908105619651923148800, 1020690003311610463765638355505358381593396977336320000, 237443634207909205360438080389756681126654524500073656592021585920000
OFFSET
0,2
LINKS
J. Overbey, W. Traves and J. Wojdylo, On the Keyspace of the Hill Cipher.
FORMULA
a(n) = (7^n - 1)*(7^n - 7)*...*(7^n - 7^(n-1)).
a(n) = A109493(n)*A027875(n). - Bruno Berselli, Jan 30 2013
MATHEMATICA
Table[Product[7^n - 7^k, {k, 0, n-1}], {n, 0, 10}] (* Vincenzo Librandi, Jan 28 2013 *)
PROG
(Magma) [1] cat [&*[(7^n - 7^k): k in [0..n-1]]: n in [1..7]]; // Bruno Berselli, Jan 28 2013
(PARI) for(n=0, 10, print1(prod(k=0, n-1, 7^n - 7^k), ", ")) \\ G. C. Greubel, May 31 2018
CROSSREFS
Column k=7 of A316622.
Sequence in context: A341872 A024086 A094036 * A209737 A209458 A209520
KEYWORD
nonn,easy
AUTHOR
Stephen G Penrice, Mar 04 2000
EXTENSIONS
More terms from Vladeta Jovovic, Mar 16 2000
STATUS
approved