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A375786
a(n) is the minimum volume of an integer-sided cuboid having the same surface as a cube with edge length n.
2
1, 8, 13, 36, 37, 104, 73, 188, 121, 252, 181, 428, 253, 540, 337, 764, 433, 828, 541, 1196, 661, 1448, 793, 1476, 937, 2024, 1093, 2160, 1261, 2592, 1441, 2628, 1633, 3464, 1837, 3884, 2053, 3708, 2281, 4796, 2521, 5148, 2773, 5616, 3037, 5436, 3313, 6660, 3601
OFFSET
1,2
COMMENTS
Conjecture: From the integer-sided cuboids with same surface 6*n^2 always the one with the smallest edge length has the minimum volume. If there are several integer-sided cuboids having the smallest edge length, then the one with the smallest second smallest edge length has the minimum volume (checked up to a(1000)).
The maximum volume is always A000578(n) = n^3.
LINKS
Felix Huber, Maple programs
Eric Weisstein's World of Mathematics, Cuboid
EXAMPLE
a(6) = 104: because from the five integer-sided cuboids (2, 2, 26), (2, 5, 14), (2, 6, 12), (3, 6, 10), (6, 6, 6) having the same surface as a cube with edge length 6 (see example in A375785) has (2, 2, 26) with 2*2*26 = 104 the smallest volume.
MAPLE
See Huber link.
CROSSREFS
KEYWORD
nonn
AUTHOR
Felix Huber, Sep 17 2024
STATUS
approved