This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
f:= proc(n) local a,b,t,T,k;
b:= 0; a:= 1; T:= -3 mod n;
for k from 1 do
t:= a+b mod n;
if t = T then return k+1 fi;
a:= b; b:= t;
od
end proc:
f(1):= 1: f(3):= 1:
select(n -> f(n) = n+6, [$1..2000]); # Robert Israel, Jun 08 2023
1044=521+523, 1044^3=1137893184=568946591+568946593.
sttpQ[n_]:=Module[{x=(n-2)/2},AllTrue[{x,x+2},PrimeQ]]; Select[Range[ 12,300000,12],sttpQ[#]&&sttpQ[#^3]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Jul 25 2017 *)
isok(n) = !(n % 2) && isprime(n/2-1) && isprime(n/2+1) && isprime(n^3/2-1) && isprime(n^3/2+1); \\ Michel Marcus, Oct 19 2013
384=191+193, 384^3=147456=73727+73729.
Select[12 Range[30000],AllTrue[{#/2+1,#/2-1,#^4/2+1,#^4/2-1},PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Feb 01 2017 *)
isok(n) = !(n % 2) && isprime(n/2-1) && isprime(n/2+1) && isprime(n^4/2-1) && isprime(n^4/2+1); \\ Michel Marcus, Oct 19 2013
Comments