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A248708
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a(n) = f(4*n+2)/(f(n-1)*f(n)*f(n+1)*f(n+2)), where f(k) = k!.
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4
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60, 12600, 2522520, 514594080, 107550162720, 22969641895200, 4995897112206000, 1103284402265073600, 246784661070292144800, 55803246694136969227200, 12736017918577260592084800, 2930174751896446667689440000, 678879630375093886522676256000, 158257286142440155623613107216000
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OFFSET
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1,1
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COMMENTS
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These are multinomial coefficients.
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LINKS
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FORMULA
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EXAMPLE
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a(2) = 10!/(1!*2!*3!*4!) = 12600.
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MATHEMATICA
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Table[(4 n + 2)!/((n - 1)! n! (n + 1)! (n + 2)!), {n, 1, 20}]
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PROG
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(Sage) [factorial(4*n + 2)/(factorial(n - 1)* factorial(n)*factorial(n + 1)*factorial(n + 2)) for n in range(1, 14)] # Stefano Spezia, Aug 16 2024
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CROSSREFS
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KEYWORD
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nonn,easy,changed
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AUTHOR
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STATUS
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approved
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