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User talk:T. D. Noe

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OEIS movie

Hi, I tried to upload the short version of your OEIS movie (converted to OGG) here, but apparently OGG is not yet on the list of permitted upload formats. For plan B — upload to commons and use it here — the short version needs a CC-BY-SA (Creative Commons BY attribution Share Alike) or similar license, CC-BY-NC (Non-Commercial) as used here won't be good enough. Is that okay with you? I could link to your sayso from commons wherever it is (not necessarily here). –Frank Ellermann 11:03, 21 April 2011 (UTC)

Look over Seq. o' th' Day for June?

Tony, when you get a chance, could you look over Template:Sequence of the Day for June 28, Template:Sequence of the Day for June 29 and Template:Sequence of the Day for June 30, and, if they meet with your approval, mark them so? Alonso del Arte 22:23, 23 May 2011 (UTC)

Hey, quick question

Why did you delete my sum comment on A000045? If it was because of the format, how would I format it? If not, why? Thank you very much for your time, my e-mail is joepshoulak@me.com .

If you're talking about edits 178 ff. [1], he didn't delete it. He moved it from the comments section to the formulas section and clarified it slightly.
See the Style Sheet for information on formatting sequences, or just look at similar entries in that and other sequences.
Charles R Greathouse IV 22:50, 6 February 2012 (UTC)

A085823

Hello,

in my recent comment to A085823 (dated 2012-04-20, sent -04-30) I proposed to change the definition to “Numbers such that all substrings are primes" instead of “Prime numbers …”, since the changed definition describes the resulting sequence correctly, and is obviously more simple in that the primality presumption is not needed.

You answered that it should be left as "primes". Otherwise someone could argue the 22 should appear. - This is not true, since 22 (which has the substrings 2, 2 and 22) has not the property that all substrings are primes.

As usual, the full string of all digits is also a substring. In the definition there is no restriction to proper substrings. As a result there is effectively no difference between that two versions “Numbers ..." and “Prime numbers ...". The only difference is in the mathematical strictness. For a mathematical site with scientific standard this seems to be not a bad argument to me.

Nevertheless, I have no problem with the old definition. It's not perfect, but it not wrong.

Greetings,

Hieronymus Fischer

A013655

This sequence is also known as the Evangelist Series, here is the footnote from Fibonacci Pitch Sets pdf:

"The Evangelists’ sequence was named so because of the occurrence of the numbers {2, 5, 7, 12} in the Evangelists’ account of Jesus feeding the multitude (Matthew 14: 17-20, John 6: 9-13, Matthew 15: 34- 37). One of its many interesting relations to the Fibonacci sequence is en = fn + 3 – fn – 2 for all n where en = the nth number in the Evangelists’ sequence and fn = the nth Fibonacci number."

The reason I mention this is that some classical composers e.g. Sofia Gubaidulina, use this series and this name. However it is almost impossible to find out what the Evangelist Series is so by mentioning this on OEIS it would help those analysing contemporary classical music find the term.

Would it be acceptable for me to add such a comment?

The original paper is Finonacci_Pitch_Sets.pdf and can be found at http://www.caseymongoven.com/writings.

Many thanks,

Ian Stewart (ianian d/ot stewart a/t virgin d/ot net)

Ian Stewart 09:55, 7 June 2012 (UTC)

A218207 to A218214

Hello,

for the sequences A218209 to A218210 I considered primes of the form p = sum(i^2,i=k..k+2) = k^2 + (k+1)^2 + (k+2)^2 = 3*k^2+6*k+5, just as for the sequences A218211 to A218212 primes of the form p = sum(i^2,i=k..k+5) = k^2 + (k+1)^2 + … + (k+5)^2 = 6*k^2+30k+55. For the process of summation I only regarded natural numbers k > 0. Hence the first prime in the first case is 29 = 2^2 + 3^2 + 4^2 for k = 2 (as mentioned in Chris K. Caldwell; G. L. Honaker, Jr.: Prime Curious!, p. 33.) and 139 = 2^2 + 3^2 + … + 7^2 for k = 2 in the second. These are the k's of sequences A027863, A027866 and the primes of sequences A027864, A027867 (for n > 0).

Therefore I think, the following sequences should read

A218209: 0, 1, 3, 4, 12, ...
A218210: 0, 1, 4, 8, 20, …
A218211: 0, 0, 4, 10, 15, …
A218212: 0, 0, 4, 14, 29, …

as I first recorded them in my entry yesterday. Otherwise the comment in A218213 and A218214 is obsolete.

See also the example in A218214 for further explanation. There the primes 2 and 5 for the sum of three consecutive squares as well as 19 and 31 for the sum of six consecutive squares are not mentioned.

Kind regards,

Martin Renner 21:28, 24 October, 2012 (CET)

Sequence A220370

Dear Sir, it looks like you contributed to approving the above sequence. However, the table of values is wrong. Could you correct it please? The values that show up on the page are okay, but not the ones you see when you click on the table link. Did you maybe include zero squares in the table? These are not counted per definition. Marko Riedel 21:49, 17 December 2012 (UTC)

A019505

Go to A019505. It looks like my conjecture that this is a subsequence of A002182 is disproven with the 64th term. Can you check to see??

A221869

I appreciate the assist very much ...due to omitted terms I wasn't even aware of the Cf sequence. --Bill McEachen 12:16, 12 April 2013 (UTC)

A195467

Wed Aug 28 12:39
T. D. Noe: This huge edit gives the impression that you do not know what you are doing!

Can't you just tell me what the problem is, when there is one? It is not easy to represent this array as a sequence, and the new representation is certainly better than representing a rectangular array by antidiagonals. There is no good way to add rectangular arrays to the OEIS, and building a staircase (usually the option that sucks least) wouldn't make sense in this case. Tilman Piesk 18:08, 28 August 2013 (UTC)

A001602

Hello, it's an honor. I wanted to ask you about a statement you made on the sequence, and if there is any reference to a proof.

"The number of times n occurs is A086597(n), the number of primitive prime factors of Fibonacci(n)"

I understand that means without multiplicity, and for composite indexed Fibonacci n as well?

I am working on updating the Wikipedia information for Fibonacci-Wieferich prime, aka Wall-Sun-Sun.

Can you please confirm, deny, or elaborate about this?

Let us suppose there is a Fibonacci Wieferich prime p2 | Fq, where q is p minus the Legendre symbol .

For n ≥ 3, Fn divides Fm iff n divides m.

This implies directly that, Fp2 | FFq

This sequence leads to absurdum:

  • F(49) ∤ F(21)
  • F(121) ∤ F(55)
  • F(169) ∤ F(377)
  • F(289) ∤ F(2584)
GCD(Fp2, FFq)= Fp
Fp2 ∤ FFq, therefore p2 ∤ Fq.

Thank you for any insights you have.--Shane Findley 06:31, 23 September 2015 (UTC)

[I have written directly to Shane Findley to answer this question. - N. J. A. Sloane 15:59, 23 September 2015 (UTC)]