OFFSET
1,1
COMMENTS
If x is a member and y is a member of this sequence or A248219 or A256342, then LCM(x,y) is a member. - Robert Israel, Mar 09 2021
LINKS
Robert Israel, Table of n, a(n) for n = 1..10000
MAPLE
filter:= proc(n) local x, k, R, p;
x:= 0; R[0]:= 0;
for k from 1 do
x:= x^2+1 mod n;
if assigned(R[x]) then return evalb(k-R[x] = 4)
else R[x]:= k
fi
od;
end proc:
select(filter, [$1..1000]); # Robert Israel, Mar 09 2021
PROG
(PARI) for(i=1, 600, A248218(i)==4&&print1(i", "))
CROSSREFS
KEYWORD
nonn
AUTHOR
M. F. Hasler, Mar 25 2015
STATUS
approved