Crisscross multiplying
sun18feb2007—07w049d13%— 08h44m00s—0utc
This really won’t save you any work at all but it’s sure to baffle casual onlookers.
At heart is just the usual distributive WP algorithm we all use when multiplying arabics WP, rearranged and visually rewritten using the immediate correspondence of crisscrosses to multiplication:
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