Dozenal divisibility tests
Daily Dozen: Thu 13 May 11EX: Dozenal has easy divisibility tests for all lower integers except 7 and X.
— Dozenal Society DSA (@dozenal) May 15, 2014
Daily Dozen: Thu 13 May 11EX: Dozenal has easy divisibility tests for all lower integers except 7 and X.
— Dozenal Society DSA (@dozenal) May 15, 2014
John Scott Russell, born today in 1808, discovered soliton waves in the canal just outside Edinburgh. http://t.co/u0glprvYAE
— ICMS Edinburgh (@ICMS_Edinburgh) May 9, 2014
For the 103rd day of the year: 103 is the reverse of 301. The same is true of their squares: 103² = 10609 and 301² = 90601
— jim wilder (@wilderlab) April 13, 2014
Al-Karaji (953-about 1029), “regarded as the first person to free algebra from geometrical operations”, born 13 Apr http://t.co/aABEYxo7KO
— Maths History (@mathshistory) April 13, 2014
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“…cool kids get under 20000…” and the 2048 tile.
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Youtube channel for the Young Academy.
On the anniversary of Napier’s death here are a couple of quotes regarding his logarithms;
Briggs said
Napper, lord of Markinston, hath set my head and hands a work with his new and admirable logarithms. I hope to see him this summer, if it please God, for I never saw a book which pleased me better or made me more wonder.
and Laplace said logs
…by shortening the labours, doubled the life of the astronomer.
Read Napier’s bio.
John Napier (1550-1617) best known for inventing logarithms but did much more, died 4 Apr http://t.co/wNKPRtKX4P
— Maths History (@mathshistory) April 4, 2014
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