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User:Charles R Greathouse IV
From OeisWiki
Trustee and Editor-in-Chief, interested primarily in computational number theory.
I can be contacted via my Talk page here, or by email: my first name (charles) at my initials (crg4) dot com. Other email addresses may work as well.
User:Charles R Greathouse IV/Averages | Early draft of an article. |
User:Charles R Greathouse IV/Chase sequences | 'Chase sequences': Axxxxxx refers to Ayyyyyy, which refers to Azzzzzz... |
User:Charles R Greathouse IV/Favorites | Some of my favorite sequences. |
User:Charles R Greathouse IV/Format | Discusses the correct format of b-files and how to repair ill-formatted b-files. |
User:Charles R Greathouse IV/Junk | Disreputable publishers, journals, etc. |
User:Charles R Greathouse IV/Keywords | Information on keywords: when to use them, new ones to add, etc. |
User:Charles R Greathouse IV/Metadata | Plans for OEIS metadata: keywords, categories, the index, etc. |
User:Charles R Greathouse IV/Pari | Some PARI/GP tools. |
User:Charles R Greathouse IV/Programs | Programs in the OEIS: types, format, etc. |
User:Charles R Greathouse IV/Projects | Other mathematical databases, fingerprint databases, and similar projects |
User:Charles R Greathouse IV/Properties | Sequence properties and classes |
User:Charles R Greathouse IV/Rule of thumb | Sequences should take 1 hour to prepare for submission. |
User:Charles R Greathouse IV/Tables of special primes | Types of primes and their densities |
User:Charles R Greathouse IV/To do | Sequences to work on and b-files to fix. |
User:Charles R Greathouse IV/Vanity | Sequences named after their discoverer. |
User:Charles R Greathouse IV/Wiki | Tools for the OEIS wiki. |
Projects:
Useful links:
- Features Wishlist, User:Russ Cox/OEIS Server Features, Suggested Projects
- Deleted sequences
- Suggested pre-submit checklist
- Requested articles
- Editing history: sequence, wiki
- References on proof attempts: P vs. NP, Riemann hypothesis
[talk]
Sequence of the Day for September 25
A002064: Cullen numbersCn = n ⋅2 n + 1, n ≥ 0 |
{ 1, 3, 9, 25, 65, 161, 385, 897, ... }
ϕ (Cn ) | (Cn − 1) |
Cn |
m |
ϕ (m) | (m − 1) |
ϕ (m) |
Sequences in the News
- September 15, 2016 Tom Greer's twin primes discovery is verified. These are currently the largest known twin primes.
- September 14, 2016 Tom Greer discovers the twin primes 2996863034895 × 2 1290000 ± 1 using PrimeGrid, TwinGen and LLR.
- January 19, 2016 Largest known term of A000043 announced: 274207281, also discovered by Curtis Cooper.
- March 2, 2014 Fredrik Johansson announces a computation of the partition number , the largest known term of A000041.
- December 6, 2013 Microsoft launches a challenge to find large non-Mersenne primes, A138837.
- May 13, 2013 H. A. Helfgott submits a proof of the weak Goldbach conjecture, i.e. for odd numbers as sums of three primes: A007963 has no more zeroes.
- January 25, 2013 Curtis Cooper discovers a new member of A000043, 57885161. Its index is not known but is at least 48.
- January 13, 2013 The winners of the contest for new sequences in the OEIS at JMM 2013 were announced: A187824, A187771, and A187761.
Complaints
I strive to live up to the highest ethical standards. If you feel that I have wrongly rejected one of your sequences (or otherwise failed to meet the expected standards), please leave a note at Complaints About Editing where it will be reviewed. I hope that in all cases you will first contact me (through the pink comment boxes, on my user page, or by email).