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A094000
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Number of n X n (0,1)-matrices with no zero rows or columns and with all rows distinct and all columns distinct, up to permutation of rows.
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2
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1, 1, 3, 29, 1015, 126651, 53354350, 74698954306, 350688201987402, 5624061753186933530, 314512139441575825493524, 62498777166571927258267336860, 44831219113504221199415663547412096
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,3
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REFERENCES
| G. Kilibarda and V. Jovovic, "Enumeration of some classes of T_0-hypergraphs", in preparation, 2004.
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FORMULA
| Main diagonal of A059202. a(n) = Sum(Stirling1(n+1, k)*binomial(2^(k-1)-1, n), k=0..n+1).
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MATHEMATICA
| f[n_] := Sum[ StirlingS1[n + 1, k] Binomial[2^(k - 1) - 1, n], {k, 0, n + 1}]; Table[ f[n], {n, 0, 12}] (from Robert G. Wilson v Jun 01 2004)
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CROSSREFS
| Cf. A059202, A048291, A088309.
Sequence in context: A117264 A065072 A088389 * A162085 A003190 A133663
Adjacent sequences: A093997 A093998 A093999 * A094001 A094002 A094003
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KEYWORD
| easy,nonn
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AUTHOR
| Goran Kilibarda, Vladeta Jovovic (vladeta(AT)eunet.rs), May 30 2004
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EXTENSIONS
| More terms from Robert G. Wilson v (rgwv(AT)rgwv.com), Jun 01 2004
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