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[2n^n+1,{n,20}],PrimeQ] (* Harvey P. Dale, Mar 27 2016 *)
for(n=1,999, ispseudoprime(p=n^n*2+1) & print1(p","))
a(2) = 9 = 3^2, a(3) = 55 = 5*11, a(4) = 513 = 3 ^ 3 * 19.
with(numtheory):for n from 0 to 50 do: x:=2*n^n + 1 : if type(x,prime)=false then print (x):else fi:od:
Select[Table[2n^n+1,{n,20}],CompositeQ] (* Harvey P. Dale, Jun 21 2015 *)
Join[{0}, Select[Range[1000], PrimeQ[2*#^# + 1] &]] (* Robert Price, Mar 27 2019 *)
is_A110932(n)=ispseudoprime(n^n*2+1) \\ M. F. Hasler, Sep 02 2012
a(1) = 1, because 2^2*3+1 = 13 is the smallest prime of this form. a(2) = 2, because 4^4*3+1 = 769 is the next smallest prime of this form. a(3) = 3, because 6^6*3+1 = 139969 is again a prime.
q:= k-> isprime(3*(2*k)^(2*k)+1): select(q, [$1..225])[]; # Alois P. Heinz, Aug 04 2025
for(i=1,9999,ispseudoprime(i^i*3+1)&print1(i/2,","))
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