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19, 57, 171, 513, 1539, 4617, 13851, 41553, 124659, 373977, 1121931, 3365793, 10097379, 30292137, 90876411, 272629233, 817887699, 2453663097, 7360989291, 22082967873, 66248903619, 198746710857, 596240132571, 1788720397713, 5366161193139, 16098483579417
(list;
graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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0,1
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COMMENTS
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Since 19^3 = 3^3+10^3+18^3, the cube of any multiple of 19 can be written as the sum of three positive cubes: (19*k)^3 = (3*k)^3 + (10*k)^3 + (18*k)^3.
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LINKS
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FORMULA
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E.g.f.: 19*exp(3*x).
a(n) = 3*a(n-1) for n > 0. (End)
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MATHEMATICA
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19*3^Range[0, 30] (* or *) NestList[3#&, 19, 30] (* Harvey P. Dale, Feb 03 2013 *)
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PROG
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(Magma) [19*3^n: n in [0..250]];
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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