OFFSET
1,2
COMMENTS
By Hensel's lemma, x^2 + x + 41 has two roots mod 41^n; their sum == -1 mod 41^n. Thus 0 <= a(n) < 41^n/2. - Robert Israel, Apr 09 2018
LINKS
Robert Israel, Table of n, a(n) for n = 1..620
MAPLE
f:= n -> min(map(t -> rhs(op(t)), [msolve(x^2+x+41, 41^n)])):
map(f, [$1..30]); # Robert Israel, Apr 09 2018
MATHEMATICA
a = {}; Do[x = 0; While[Mod[x^2 + x + 41, 41^n] != 0, x++ ]; AppendTo[a, x]; Print[{n, x, x^2 + x + 41, (x^2 + x + 41)/41^n}], {n, 1, 6}]; a (* Artur Jasinski *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Artur Jasinski, Nov 06 2008
EXTENSIONS
More terms from Robert Israel, Apr 09 2018
STATUS
approved