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A356203
a(n) is the first component x of the distance vector (x,y) in an oblique 120-degree coordinate system, 0 <= y <= x, between two nodes of an infinite triangular lattice of one-ohm resistors, such that the resistance R between the two nodes is as close as possible to n ohms, i.e., abs(R - n) is minimized. y is A356204(n).
2
0, 43, 9615, 2299822, 507491696, 118805048562, 25315296119626, 5959615271620724
OFFSET
0,2
EXAMPLE
n x y R(x,y) - n
0 0 0 0
1 43 18 5.033*10^(-6)
2 9615 2536 1.848*10^(-10)
3 2299822 1136101 -3.120*10^(-14)
4 507491696 119227930 5.751*10^(-19)
5 118805048562 33636581266 5.618*10^(-23)
6 25315296119626 1774960492720 8.406*10^(-29)
7 5959615271620724 685318499093455 2.526*10^(-32)
CROSSREFS
Cf. A356201, A356202 (similar for square lattice).
Sequence in context: A147522 A183489 A361892 * A184144 A262856 A302484
KEYWORD
nonn,hard,more
AUTHOR
Hugo Pfoertner, Aug 13 2022
STATUS
approved