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A321492
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Numbers that can be written as (x + y)(x^2 + y^2), x > y > 0, in at least two ways.
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2
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12325, 98600, 117720, 146705, 206312, 263840, 332775, 378505, 400945, 500200, 651456, 687245, 734400, 741845, 773800, 788800, 799240, 941760, 1173640, 1327360, 1533195, 1540625, 1650496, 1735105, 1836680, 1943240, 2048320, 2050880, 2110720, 2217280, 2662200, 2704360, 2965685
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listen;
history;
text;
internal format)
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OFFSET
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1,1
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COMMENTS
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See A321491 for numbers of the form (x+y)(x^2+y^2) = A321490(x,y) with x > y > 0.
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LINKS
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EXAMPLE
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12325 = (13+16)(13^2+16^2) = (3+22)(3^2+22^2).
98600 = (26+32)(26^2+32^2) = (6+44)(6^2+44^2).
117720 = (21+39)(21^2+39^2) = (8+46)(8^2+46^2).
146705 = (24+41)(24^2+41^2) = (14+47)(14^2+47^2).
206312 = (15+53)(15^2+53^2) = (32+42)(32^2+42^2).
263840 = (6+62)(6^2+62^2) = (33+47)(33^2+47^2).
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PROG
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(PARI) A321492_list(L=1e6)={my(S=[], T=List(), t); for(m=2, sqrtn(L, 3), while(#S&&S[1]<=m^3, S=S[^1]); for(n=1, m-1, if(L<t=(m+n)*(m^2+n^2), next(2), setsearch(S, t), listput(T, t); S=setminus(S, [t]), S=setunion(S, [t])))); Set(T)}
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CROSSREFS
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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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