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A338727
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a(n) = C(n+1)^2 - 2*C(n+1)*C(n) + C(n)^2, where C() is a Catalan number.
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2
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1, 1, 9, 81, 784, 8100, 88209, 1002001, 11778624, 142420356, 1763160100, 22268399076, 286105172544, 3730846771600, 49286086364025, 658580586980625, 8890060997894400, 121099761397088100, 1663131325207760100, 23009839285003272900, 320486852887891560000, 4491184012659823424400, 63291012091734041000100
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OFFSET
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0,3
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LINKS
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FORMULA
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D-finite with recurrence (n+2)^2*(n-1)^2*a(n) -4*n^2*(2*n-1)^2*a(n-1)=0. - R. J. Mathar, Dec 11 2020
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MAPLE
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if n = 0 then
1;
else
end if;
end proc:
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CROSSREFS
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Equals A000245(n) squared for n >= 1.
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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