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[Table[4^n-n,{n,200}],PrimeQ] (* Harvey P. Dale, Mar 16 2015 *)
forstep(n=2,10^4,2,if(ispseudoprime(7^n-n),print1(n,", "))); /* Joerg Arndt, Apr 07 2013 */
import java.math.BigInteger; public class A224471 { public static void main (String[] args) { BigInteger b8 = BigInteger.valueOf(8); BigInteger m = BigInteger.valueOf(64); for(long n=1; ; n+=2) { BigInteger b = b8.subtract(BigInteger.valueOf(n)); if (b.isProbablePrime(2)) { if (b.isProbablePrime(80)) System.out.printf("%d\n", n); } b8 = b8.multiply(m); } } }
forstep(n=1,10^4,2,if(ispseudoprime(8^n-n),print1(n,", "))); /* Joerg Arndt, Apr 07 2013 */
Select[Range[1000], PrimeQ[9^# - #] &] (* Alonso del Arte, Apr 11 2013 *)
is(n)=ispseudoprime(9^n-n) \\ Charles R Greathouse IV, Jun 13 2017
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