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A335715
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Squarefree numbers m such that the equation x*(x+1)*(x+2) = m*y^2 has more than one solution (x,y) with x>0 and y>0.
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3
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6, 210, 546, 915, 1785, 7230, 13395, 16206, 17490, 20930, 76245, 104006, 228486, 508530, 563766
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OFFSET
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1,1
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COMMENTS
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7453355, 9147666, 19073886, 61622814, 648402306, 22023958326, 748181603526 are also terms. - Jinyuan Wang, Jul 28 2020
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LINKS
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EXAMPLE
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6 is a term since x*(x+1)*(x+2) = 6*y^2 has 3 positive integer solutions : (1,1), (2,2) and (48,140) that give (1,1) and (24,70) for s*(s+1)*(2s+1) = 6*t^2 with a (x=2s, y=2t) variable change (see A000330 where A000330(n) = n*(n+1)*(2*n+1)/6).
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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