OFFSET
3,1
COMMENTS
Similar to A211223 but using anti-divisors.
EXAMPLE
sigma*(127)=sigma*(45)+sigma*(82) that is 212=86+126.
In more than one way:
sigma*(133)=sigma*(50)+sigma*(83)=sigma*(52)+sigma*(81) that is
204=80+124=94+110.
MAPLE
with(numtheory);
A210732:=proc(q)
local a, b, c, i, j, k, n;
for n from 3 to q do
a:=0;
for k from 2 to n-1 do if abs((n mod k)-k/2)<1 then a:=a+k; fi; od;
for i from 1 to trunc(n/2) do
b:=0; c:=0;
for k from 2 to i-1 do if abs((i mod k)-k/2)<1 then b:=b+k; fi; od;
for k from 2 to n-i-1 do if abs(((n-i) mod k)-k/2)<1 then c:=c+k; fi; od;
if a=b+c then print(n); break; fi;
od;
od; end:
A210732(10000);
CROSSREFS
KEYWORD
nonn
AUTHOR
Paolo P. Lava, May 10 2012
STATUS
approved