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A230400
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Numbers n such that n = abc = 2(ab+ac+bc) for some positive integers a,b,c.
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2
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OFFSET
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1,1
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COMMENTS
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Otherwise said: Volumes of integer-sided cubes equal to their surface area (assuming dimensionless unit of length).
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LINKS
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EXAMPLE
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The triples (a,b,c) ordered by largest member(s) are (6,6,6), (8,8,4), (10,5,5), (12,6,4), (12,12,3), (15,10,3), (18,9,3), (20,5,4), (24,8,3), (42,7,3).
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PROG
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(PARI) L=[]; for(a=1, 99, for(b=1, a, for(c=1, b, a*b*c==2*(a*b+b*c+a*c)&&!printf("(%d, %d, %d), ", a, b, c)&&L=concat(L, a*b*c)))); vecsort(L)
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CROSSREFS
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KEYWORD
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nonn,fini,full
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AUTHOR
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STATUS
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approved
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