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.
Select[ Prime[ Range[1, 100000] ], PrimeQ[ (9^# + 8^#)/17 ]& ]
is(n)=isprime((9^n+8^n)/17) \\ Charles R Greathouse IV, Feb 17 2017
Select[ Prime[ Range[1, 100000] ], PrimeQ[ (10^# + 9^#)/19 ]& ]
is(n)=isprime((10^n+9^n)/19) \\ Charles R Greathouse IV, Feb 17 2017
For n=4, the expression (2^k + (2n-1)^k)/(2n+1) takes on values 1, 53/9, 39, 2417/9, and 1871 for k=1..5. Since 1871 is the first prime number to occur, a(4) = 5.
Do[k = 1; While[ !PrimeQ[(2^k + (2n-1)^k)/(2n+1)], k++ ]; Print[k], {n, 100}] (* Ryan Propper, Mar 29 2007 *)
Select[Prime[Range[1, 100000]], PrimeQ[(15^# + 2^#)/17]&]
forprime(p=3,10^6, if(ispseudoprime((15^p + 2^p)/17), print1(p,", ") ) ); \\ Joerg Arndt, Jul 29 2013
Select[Prime[Range[1, 100000]], PrimeQ[(13^# + 2^#)/15]&]
forprime(p=3,10^6, if(ispseudoprime((13^p + 2^p)/15), print1(p,", ") ) ); \\ Joerg Arndt, Jul 29 2013
Select[ Prime[ Range[1, 100000] ], PrimeQ[ (9^# + 4^#)/13 ]& ]
is(n)=ispseudoprime((9^n+4^n)/13) \\ Charles R Greathouse IV, Jun 13 2017
[n: n in [1..10000] |IsPrime((9^n+7^n)/16)]
select(n->isprime((9^n+7^n)/16),[seq(n,n=1..10000,2)]); # Muniru A Asiru, Mar 27 2018
Select[Range[1, 10000], PrimeQ[(9^n+7^n)/16] &]
forprime(n=3, 10000, if(isprime((9^n+7^n)/16), print1(n, ", ")))
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