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A006382
Number of n X 4 binary matrices under row and column permutations and column complementations.
(Formerly M3814)
9
1, 1, 5, 11, 41, 101, 301, 757, 1981, 4714, 11133, 24763, 53818, 111941, 226857, 444260, 848620, 1576226, 2862426, 5077454, 8827758, 15043096, 25183794, 41434222, 67108437, 107051463, 168402958, 261384026, 400684767, 606936536
OFFSET
0,3
REFERENCES
M. A. Harrison, On the number of classes of binary matrices, IEEE Trans. Computers, 22 (1973), 1048-1051.
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
LINKS
Index entries for linear recurrences with constant coefficients, signature (6, -13, 10, 4, -14, 25, -46, 53, -36, 8, 44, -111, 138, -123, 106, -54, -66, 181, -238, 259, -220, 98, 36, -150, 280, -352, 280, -150, 36, 98, -220, 259, -238, 181, -66, -54, 106, -123, 138, -111, 44, 8, -36, 53, -46, 25, -14, 4, 10, -13, 6, -1).
FORMULA
G.f. : (1/(1 - x^1)^16 + 51/(1 - x^2)^8 + 12/(1 - x^1)^8/(1 - x^2)^4 + 84/(1 - x^4)^4 + 12/(1 - x^1 )^4/(1 - x^2)^6 + 32/(1 - x^1)^4/(1 - x^3)^4 + 96/(1 - x^2)^2/(1 - x^6)^2 + 48/(1 - x^1)^2/(1 - x^2)^1/(1 - x^4)^3 + 48/(1 - x^8)^2)/384.
EXAMPLE
Representatives of the five classes of 2 X 4 binary matrices are:
[ 1 1 1 1 ] [ 1 1 1 0 ] [ 1 1 0 1 ] [ 1 0 1 1 ] [ 0 1 1 1 ]
[ 1 1 1 1 ] [ 1 1 1 1 ] [ 1 1 1 0 ] [ 1 1 0 0 ] [ 1 0 0 0 ]
CROSSREFS
Column k=4 of A363349.
Sequence in context: A159049 A343712 A047976 * A295504 A055113 A260268
KEYWORD
nonn
EXTENSIONS
Entry revised by Vladeta Jovovic, Aug 05 2000
STATUS
approved