Primes which contain only one odd digit: Difference between revisions
Primes which contain only one odd digit (view source)
Revision as of 18:06, 8 September 2021
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=== stretch ===
Fast skip from 11 direct to 20+, from 101 direct to 200+, etc. Around forty times faster than the above would be, but less than twice as fast as it would be without such skipping.<br>
Of course the last digit must/will be odd for all primes (other than 2 which has no odd digit anyway), and ''all'' digits prior to that must be even, eg 223 or 241, and not 257 or 743.
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<span style="color: #008080;">with</span> <span style="color: #008080;">javascript_semantics</span>
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