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A053293 Number of nonsingular n X n matrices over GF(7). 14
1, 6, 2016, 33784128, 27811094169600, 1122211189922928537600, 2218959336124989671614429593600, 214992513152176999576908105619651923148800, 1020690003311610463765638355505358381593396977336320000, 237443634207909205360438080389756681126654524500073656592021585920000 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..30

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.

Cf. A002884, A003790, A027875, A053290-A053292, A109493.

Sequence in context: A341872 A024086 A094036 * A209737 A209458 A209520

Adjacent sequences: A053290 A053291 A053292 * A053294 A053295 A053296

KEYWORD

nonn,easy

AUTHOR

Stephen G. Penrice (spenrice(AT)ets.org), Mar 04 2000

EXTENSIONS

More terms from Vladeta Jovovic, Mar 16 2000

STATUS

approved

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Last modified December 2 18:40 EST 2022. Contains 358510 sequences. (Running on oeis4.)