Magnanimous numbers: Difference between revisions

<lang perl6>my @magnanimous = lazy flat ^10, (10 .. 1001).hyper.map( {

my int $last;

(1 ..^ .chars - 1).map: -> \c { ++$last = 1 and last unless (.substr(0,c) + .substr(c)).is-prime }

(1002 .. ∞).hyper.map: {

# optimization for numbers > 1001; First and last digit can not both be even or both be odd

next if (.substr(0,1) % 2 + .substr(*-1) % 2) %% 2;

my int $last;

(1 ..^ .chars - 1).map: -> \c { ++$last = 1 and last unless (.substr(0,c) + .substr(c)).is-prime }