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A322042
Maximum edge-distance of a point in the quotient graph E/nE from the origin (see A322041 for further information).
2
0, 1, 2, 2, 3, 4, 4, 5, 6, 6, 7, 8, 8, 9, 10, 10, 11, 12, 12, 13, 14, 14, 15, 16, 16, 17, 18, 18, 19, 20, 20, 21, 22, 22, 23, 24, 24, 25, 26, 26, 27, 28, 28, 29, 30, 30, 31, 32, 32, 33, 34, 34, 35, 36, 36, 37, 38, 38, 39, 40, 40, 41, 42, 42
OFFSET
1,3
LINKS
FORMULA
Conjectures from Colin Barker, Dec 06 2018: (Start)
G.f. = x(1+x)/(1-x-x^3+x^4) [Simplified by N. J. A. Sloane, Dec 06 2018]
a(n) = a(n-1) + a(n-3) - a(n-4) for n>4.
(End)
Conjecture: a(n) = n - ceiling(n/3) = A004523(n).
MAPLE
hist2:=proc(n) local A, i, j, m, d1, d2, d3, d4;
A:=Array(0..n, 0);
for i from 0 to n-1 do
for j from 0 to n-1 do
d1:=i+j;
d2:=n-i;
d3:=2*n-i-j;
d4:=n-j;
if i+j<n then
m:=min(d1, d2, d3, d4);
elif i+j=n then m:=min(i, j);
else
m:=min(d1, i, j, d3);
fi;
A[m]:=A[m]+1;
od: od:
R:=0;
for i from 0 to n-1 do if A[i] <> 0 then R:=i; fi; od:
R;
end;
RR:=[];
for n from 1 to 100 do RR:=[op(RR), hist2(n)]; od: RR;
CROSSREFS
Cf. A322041.
Sequence in context: A156301 A195124 A032509 * A004523 A038372 A121930
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Dec 06 2018
STATUS
approved