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A005724
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Quadrinomial coefficients.
(Formerly M3148)
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0
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3, 40, 546, 7728, 112035, 1650792, 24608948, 370084832, 5603730876, 85316186400, 1304770191802, 20029132137840, 308437355259930, 4762695514958640, 73716196036213800, 1143325208566357440, 17765127399780725316, 276484586847524844768, 4309270265307160983144
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OFFSET
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1,1
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REFERENCES
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L. Comtet, Advanced Combinatorics, Reidel, 1974, p. 78.
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
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LINKS
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FORMULA
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MAPLE
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seq(coeff((1+x+x^2+x^3)^(2*n), x, 3*n-1), n=1..30); # Robert Israel, Aug 15 2016
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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