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A078201 Smallest prime of the form n^k + k^n, or 0 if no such prime exists. 3
2, 3, 17, 5, 59604644783353249, 7, 4318114567396436564035293097707729426477458833, 205688069665150755269371147819668813122841983204711281293004769, 593, 11 (list; graph; refs; listen; history; text; internal format)
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
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
KEYWORD
hard,nonn
AUTHOR
Amarnath Murthy, Nov 21 2002
EXTENSIONS
Extended and updated by Derek Orr, Aug 10 2014
STATUS
approved

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Last modified March 2 10:43 EST 2024. Contains 370466 sequences. (Running on oeis4.)