A078201 Smallest prime of the form n^k + k^n, or 0 if no such prime exists.

2, 3, 17, 5, 59604644783353249, 7, 4318114567396436564035293097707729426477458833, 205688069665150755269371147819668813122841983204711281293004769, 593, 11

Offset

1,1

Comments

If p is a prime then a(p-1) = p, with k = 1.

a(11) has 3229 digits and is too long to include. See A243147 for k-values. - Derek Orr, Aug 10 2014

Links

Table of n, a(n) for n=1..10.

R. J. Cano (updated by Derek Orr), Additional Information

Example

a(3) = 3^2 + 2^3 = 17.
a(4) = 4^1 + 1^4 = 5.

Prog

See "Additional Information" in links.
(PARI)
a(n)=k=1; while(!ispseudoprime(n^k+k^n), k++); return(n^k+k^n)
vector(10, n, a(n)) \\ Derek Orr, Aug 10 2014

Crossrefs

Sequence in context: A029913 A073125 A171240 * A361104 A090913 A176236

Adjacent sequences: A078198 A078199 A078200 * A078202 A078203 A078204

Keyword

hard,nonn

Author

Amarnath Murthy, Nov 21 2002

Extensions

Extended and updated by Derek Orr, Aug 10 2014

Status

approved