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Search: id:A000489
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A000489 Card matching.
(Formerly M5025 N2168)
+0
4
1, 16, 435, 7136, 99350, 1234032, 14219212, 155251840, 1628202762, 16550991200, 164111079110, 1594594348800, 15235525651840, 143518352447680, 1335670583147400, 12301278983461376, 112264111607438906 (list; graph; listen)
OFFSET

1,2

REFERENCES

J. Riordan, An Introduction to Combinatorial Analysis, Wiley, 1958, p. 193.

LINKS

Index entries for sequences related to card matching

FORMULA

a(n)=3binomial(n, 3)*sum(binomial(n, k+3)*binomial(n, k)*binomial(n-3, k), k=0..n-3) +6n*binomial(n, 2)*sum(binomial(n, k+1)*binomial(n-1, k+2)*binomial(n-2, k), k=0..n-3)+n^3*sum(binomial(n-1, k)^3, k=0..n-1).

CROSSREFS

Cf. A000279, A000535.

Adjacent sequences: A000486 A000487 A000488 this_sequence A000490 A000491 A000492

Sequence in context: A143039 A111921 A118994 this_sequence A075852 A068792 A113674

KEYWORD

nonn

AUTHOR

njas

EXTENSIONS

More terms from Vladeta Jovovic (vladeta(AT)Eunet.yu), Apr 26 2000

More terms from Emeric Deutsch (deutsch(AT)duke.poly.edu), Feb 19 2004

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Last modified October 11 13:47 EDT 2008. Contains 144830 sequences.


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