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Search: id:A162868
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| A162868 |
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Lowest common multiple of all squares and all sums of two squares up to n^2+n^2 |
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+0
1
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| 1, 2, 40, 4680, 1591200, 1891936800, 4270101357600, 11089453225687200, 32565776278494961756800, 28429922691126101613686400, 42204464874461454985621846571472000
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OFFSET
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0,2
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COMMENT
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Also the lowest common multiple of all rows of triangle A069011 up to the nth row.
LCM(0) is taken to be 1, which follows from 0! = 1
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FORMULA
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a(n) = LCM({ x,y:N | 0 <= x <= y <= n; x^2+y^2 })
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EXAMPLE
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a(3) = LCM(0^2+0^2; 0^2+1^2, 1^2+1^2; 0^2+2^2, 1^2+2^2, 2^2+2^2; 0^2+3^2, 1^2+3^2, 2^2+3^2, 3^2+3^2) = LCM(0; 1, 2; 4, 5, 8; 9, 10, 13, 18) = 4680
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CROSSREFS
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Cf. A069011, A001481
Sequence in context: A060079 A052502 A104134 this_sequence A059476 A062769 A033841
Adjacent sequences: A162865 A162866 A162867 this_sequence A162869 A162870 A162871
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KEYWORD
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easy,nonn
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AUTHOR
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Carl R. White (oeisfan(AT)phodd.net), Jul 15 2009
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