Going Postal
MENU
  • Home ►
    • Contact
    • Privacy Policy
    • Blog
  • Politics ►
    • Authoritarianism
    • Capitalism
    • Communism
    • Conservatives
    • Elections
    • European Union
    • Labour
    • Peace
    • Socialism
    • Terrorism
    • War
    • US
  • Economics ►
    • Business
    • Finance
    • Trading
  • Science ►
    • Engineering
    • Geology
    • Health
    • Physics
    • Mathematics
    • Space
    • Technology
  • History ►
    • English Civil War
    • 18th Century
    • 19th Century
    • 20th Century
    • WW I
    • WW II
    • The Cold War
  • Literature ►
    • Biography
    • Book Reviews
    • Fiction
    • Mystery
    • Poetry
    • Satire
    • Thriller
  • Forums ►
    • Campaigning
    • Competitions
    • Culture
    • Current Affairs
    • Elections
    • GP Events
    • Media Shows & Appearances
    • Publishing
    • Welcome
  • Merchandise ►
    • Trump Mugs and Tee Shirts
    • Custom Mug
    • GP Mugs
    • GP Coasters
    • GP Books
    • GP Keyrings
  • Home
    • Contact
    • Privacy Policy
    • Blog
  • Politics
    • Authoritarianism
    • Capitalism
    • Communism
    • Conservatives
    • Elections
    • European Union
    • Labour
    • Peace
    • Socialism
    • Terrorism
    • War
    • US
  • Economics
    • Business
    • Finance
    • Trading
  • Science
    • Engineering
    • Geology
    • Health
    • Physics
    • Mathematics
    • Space
    • Technology
  • History
    • English Civil War
    • 18th Century
    • 19th Century
    • 20th Century
    • WW I
    • WW II
    • The Cold War
  • Literature
    • Biography
    • Book Reviews
    • Fiction
    • Mystery
    • Poetry
    • Satire
    • Thriller
  • Forums
    • Campaigning
    • Competitions
    • Culture
    • Current Affairs
    • Elections
    • GP Events
    • Media Shows & Appearances
    • Publishing
    • Welcome
  • Merchandise
    • Trump Mugs and Tee Shirts
    • Custom Mug
    • GP Mugs
    • GP Coasters
    • GP Books
    • GP Keyrings

Primes

OldTrout, Going Postal
18th Century

Sophie Germain Primes and Cunningham Chains

28th September 2020 OldTrout 2231 Comments

A Sophie Germain prime is a prime number such that is also a prime number. That is, ,  where and are both prime.  For example, . The sequence begins Sophie Germain () explored these primes [more…]

Mathematics

The Infinity of the Primes

21st September 2020 OldTrout 2521 Comments

Euclid’s Elements, Book IX, Proposition 20. Theorem : Prime numbers are more than any assigned multitude of prime numbers. That is, there are infinitely many primes. Proof : Suppose that there are primes : Let [more…]

Hobbies

From a Sum to a Product

20th January 2020 OldTrout 1946 Comments

In The Basel Problem we saw that Euler answered the question by showing that the sum of the reciprocals of the square numbers is equal to . That is The partial sums slowly converge to [more…]

Mathematics

Wilson’s Theorem

2nd December 2019 OldTrout 1974 Comments

Wilson’s Theorem is a test for primality.  It is inefficient for large numbers since factorials () grow very fast.  Nevertheless, it has its uses because of its simplicity. It was conjectured by Wilson and published [more…]

Mathematics

A Triangle

4th November 2016 OldTrout 0 Comments

This is Klauber’s Triangle : – He produced it in the 1930s.  The underlying numbers are the natural numbers ℕ and are arranged as follows : – 1 2   3   4 5   6   7   8   [more…]

Latest Articles

  • Fabulously Flamboyant Friday – A Postcard From Cannes
    27th June 2025 2168 Comments
  • Always Worth Saying’s Question Time Review
    27th June 2025 2247 Comments
  • Jinnie
    Jinnie’s Story, Book Eight – Chapter Seventeen
    26th June 2025 2408 Comments
  • Book Review: The Last Murder at the End of the World by Stuart Turton
    26th June 2025 2442 Comments
  • Playing With Electricity – Part 3
    25th June 2025 2407 Comments
  • Bash 2025 Weekend
    25th June 2025 2556 Comments
  • A (Burts’ Eye) View From The Greenhouse; Feminism Or Infanticide
    24th June 2025 2181 Comments

GP on Twitter

Tweets by GoingPostalBlog

Elsewhere on GP

  • The Swaling, Part Thirty Five

    26th December 2020 1788 Comments
    “Type Tammy-May Trevallion into social media,” I instructed Rose who was in charge of the keyboard at our computer terminal in the underground communications room at the British High Commission, at the better end of [more...]
  • Postcard From Birmingham, Part Eight

    2nd November 2024 1837 Comments
    Puffins will be devasted to read this is the last episode of Postcard From Birmingham. But thrilled to hear myself and Mrs AWS have been saving up our pennies and coordinating our days off to [more...]
  • Desert Mysteries, Part Two

    22nd May 2024 2843 Comments
    In Part 1, I described how, from the signatures on the front cover of a June 1939 edition of “Blackwood’s Magazine” purchased from an antiques fair, I found that the original owner, Edward Davis Moore, [more...]
  • Going-Postal Eurovision Song Contest Special

    11th May 2024 2694 Comments
    Who could have thought in the middle years of the twentieth century that the then-nascent Eurovision Song Contest could, a mere seven decades hence, be described by serious commentators as ‘noncing s***’? Albeit the commentator [more...]
  • Crimean War, Part Two

    23rd December 2021 3308 Comments
    In 1954, as the centenary of the end of the Crimean War approached, my uncle John Alldridge produced a series of articles for the Manchester Evening News which vividly described that campaign. In this article, [more...]

Articles by Author

  • 70s_girl
  • 1642again
  • 10210ken
  • Æthelberht
  • Alexsandr too
  • Always Worth Saying
  • Ancient Mariner
  • Ang Ryman
  • Annie Dee
  • AW Kamau
  • Bark Kantatas
  • Barbican
  • Bassman
  • Bergen
  • Beware of Geeks bearing GIFs
  • Bill Quango MP
  • Blown Periphery
  • Bobo
  • Chrissie
  • Churchills Shark
  • Colin Cross
  • Colliemum
  • Columba Palumbus
  • Cynic
  • Dalester
  • DH
  • Dixie
  • DJM
  • Dorset Knob
  • Doxie
  • Dr Mike Finnley
  • EJ – Wankpuffin
  • El Cnutador
  • Emile Woolf
  • Eraser of Love
  • Foxoles
  • Gillygangle
  • Gmbd
  • Godfrey Bloom
  • Grimy Miner
  • GrumpyAngler
  • Guardian Council
  • Ivory Cutlery
  • James Dalton
  • Jethro
  • Jerry F
  • Jerry Mandarin
  • JimmySP
  • Jim Walshe
  • Joe Slater
  • Joe Williams
  • John Booth
  • John Tull
  • Jonathon Davies
  • Judas was paid
  • Katabasis
  • Kent
  • Kipper
  • LetEnglandShake
  • Lugosi
  • Madam Revenant
  • Martin Mezger
  • Mr QM
  • Nautilus
  • NeverUpToTheJob
  • Noix
  • Northern man
  • Oddanatomy
  • OldTrout
  • Ozymandias
  • Paul Wicker
  • Phil the test manager
  • Rat Catcher
  • RedBudgie
  • Reggie
  • Roger Ackroyd
  • Rookwood
  • Ross
  • SharpieType301
  • Shibusa
  • Sunshine & Showers
  • Sweaty Dave
  • Tachybaptus
  • The Black Swan
  • The Buttscratcher Jimmy
  • Tom Pudding
  • Verax Cincinnatus
  • Viciousbutfair
  • Vir Cantium
  • \/()43 |_|K19
  • well_chuffed
  • William
  • WorthingGooner
  • Wycombewanderer

Archives

Contribute to GP

If you wish to make a contribution small and often would be preferable. Paypal accepts all sorts of payment methods.




In Pictures

  • Jinnie
  • Magnetic recording tapes.
Meta
  • Log in
  • Entries feed
  • Comments feed
  • WordPress.org
Sitemap
  • Home
  • Bash 2025
  • About
  • Contact
  • Support and Subscriptions
  • Moderation philosophy and policy
  • Privacy Policy
  • Disqus Help Page

Copyright © 2025 | MH Magazine WordPress Theme by MH Themes