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A086206
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Number of n X n matrices with entries in {0,1} with no zero row and with zero main diagonal.
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2
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OFFSET
| 1,3
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FORMULA
| a(n) = (2^(n-1)-1)^n = Sum_{k=0..n} (-1)^k*binomial(n, k)*2^((n-k)*(n-1)).
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MAPLE
| with(combinat): a:=n->(mul((stirling2(n, 2)), j=1..n)): seq(a(n), n=1..10); - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Oct 03 2007
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CROSSREFS
| Cf. A055601, A086193.
a(n) = A092477(n, n-1).
Sequence in context: A017307 A167725 A060629 * A017427 A050644 A048567
Adjacent sequences: A086203 A086204 A086205 * A086207 A086208 A086209
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KEYWORD
| easy,nonn
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AUTHOR
| Vladeta Jovovic (vladeta(AT)eunet.rs), Aug 27 2003
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