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A120573
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a(n) = n^5 + 3n^3 + 2n = n(n^2+1)(n^2+2).
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3
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6, 60, 330, 1224, 3510, 8436, 17850, 34320, 61254, 103020, 165066, 254040, 377910, 546084, 769530, 1060896, 1434630, 1907100, 2496714, 3224040, 4111926, 5185620, 6472890, 8004144, 9812550, 11934156, 14408010, 17276280, 20584374, 24381060
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OFFSET
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1,1
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COMMENTS
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Largest area of any triangle with integer sides a <= b <= c and inradius n. Triangle has sides (n^2+2, n^4+2n^2+1, n^4+3n^2+1).
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LINKS
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MAPLE
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with(combinat):seq(lcm(fibonacci(4, n), fibonacci(3, n)), n=1..30); # Zerinvary Lajos, Apr 20 2008
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MATHEMATICA
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LinearRecurrence[{6, -15, 20, -15, 6, -1}, {6, 60, 330, 1224, 3510, 8436}, 30] (* Harvey P. Dale, Aug 14 2023 *)
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CROSSREFS
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See A120062 for sequences related to integer-sided triangles with integer inradius n.
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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