15 lines
415 B
Raku
15 lines
415 B
Raku
use ntheory ":all";
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sub isltrunc {
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my $n = shift;
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return (is_prime($n) && $n !~ /0/ && ($n < 10 || isltrunc(substr($n,1))));
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}
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sub isrtrunc {
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my $n = shift;
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return (is_prime($n) && $n !~ /0/ && ($n < 10 || isrtrunc(substr($n,0,-1))));
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}
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for (reverse @{primes(1e6)}) {
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if (isltrunc($_)) { print "ltrunc: $_\n"; last; }
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}
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for (reverse @{primes(1e6)}) {
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if (isrtrunc($_)) { print "rtrunc: $_\n"; last; }
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}
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