OFFSET
1,2
COMMENTS
Numbers k such that Sum_{1<=j<=k/2, j and k coprime} (k-j mod j) <= k.
Conjecture: these are all the terms.
The terms with A340740(k) = k are 19 and 48.
EXAMPLE
a(7) = 7 is a term because A340740(7) = 2 <= 7.
MAPLE
f:= proc(n) local k;
add(`if`(igcd(k, n)=1, n mod k, 0), k=1..floor(n/2))
end proc:
select(t -> f(t) <= t, [$1..1000]);
CROSSREFS
KEYWORD
nonn,more
AUTHOR
J. M. Bergot and Robert Israel, Mar 16 2021
STATUS
approved