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User:James G. Merickel

I see no point in saying much here. A lot of what I have submitted is interesting, but none very useful. Some shows I know something that is useful, but most of it doesn't, while on the other hand this matters little. I enjoy working on my submissions. Sometimes people agree what I submit is interesting, but mostly all I can really say about it is it was good enough to be published here. I'm certain more than half of it is saving somebody somewhere the task of repeating my work independently. Some is probably too obscure for that.James G. Merickel 00:42, 23 July 2015 (UTC)

Edits to my talk space are more likely to be read soon than an email. The address here is only infrequently opened.

HILARIOUS ALMOST-COINCIDENCE COINCIDENCE

Run the following program that seeks 4-fold 7-digit palindromes through when 35, the upper base -- base of a stipulated-as-known 7-digit palindrome -- is printed. Then repeat this with '>=' replaced by '>'. See the term that could have been, among 3-fold 7-palindromes, 5435700077. It is only 2-fold. Seventh term and first prime it would have been, among intrinsically 3-fold 7-palindromes. (The program doesn't calculate the 1st because it doesn't satisfy a base condition to possibly be 4-fold.) This PARI program: { b=11;while(1,

L=(b-3)^7;b3=b^3;Lk=L\b3;for(k=b3,Lk,
n=k;m=k\b;n*=b;n+=m%b;n*=b;m\=b;
n+=m%b;n*=b;m\=b;n+=m;c=1;B=b-1;
while(n<B^7,
f=1;u=n;for(i=1,3,
u=(u-(u%B)*(1+B^(8-2*i)))/B;
if(u<0,f=0;break(),
if(u>=B^(7-2*i),
f=0;break())));
c+=f;B--);
if(c>2,print1(n":"c" ")));
print1(b" ");b++)

}

Apologies for the style. The 7th term actually is the first prime, but is not as impressive-looking as a coincidence: 5798279363 in decimal.James G. Merickel 19:49, 9 August 2015 (UTC) Wow, nearly erased this thinking I had goofed. 11325719295 comes out at base 30 as the 7th to do so when this is modified. But it's bigger.James G. Merickel 22:50, 9 August 2015 (UTC)