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 A230400 Numbers n such that n = abc = 2(ab+ac+bc) for some positive integers a,b,c. 1
 216, 250, 256, 288, 400, 432, 450, 486, 576, 882 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Otherwise said: Volumes of integer-sided cubes equal to their surface area (assuming dimensionless unit of length). The sequence is a finite subsequence of A055744, A069167, A073539, A090779 and A137845. LINKS "Mathematically possible", Volume = Surface Area?, on facebook.com. EXAMPLE 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). PROG (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) CROSSREFS Cf. A229941. Sequence in context: A176766 A018863 A003998 * A001239 A184088 A205191 Adjacent sequences:  A230397 A230398 A230399 * A230401 A230402 A230403 KEYWORD nonn,fini,full AUTHOR M. F. Hasler, Oct 18 2013 STATUS approved

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Last modified January 23 07:07 EST 2020. Contains 331168 sequences. (Running on oeis4.)