OFFSET
0,1
COMMENTS
If p is prime, then R_p (see A002275) is a term, so the sequence is infinite. - Marius A. Burtea, Sep 18 2019
LINKS
Marius A. Burtea, Table of n, a(n) for n = 0..5000
EXAMPLE
10 is a term: 10 -> 1^1 + 0^0 = 2 (prime).
289 is a term: 289 -> 2^2 + 8^8 + 9^9 = 404197709 (prime).
MAPLE
q:= n-> (l-> isprime(add(i^i, i=l)))(convert(n, base, 10)):
select(q, [$0..1000])[]; # Alois P. Heinz, Sep 18 2019
MATHEMATICA
sopQ[n_] := PrimeQ[Total[#^# & /@ (IntegerDigits[n] /. {0 -> 1})]]; Select[Range[625], sopQ[#] &] (* Jayanta Basu, Jun 25 2013 *)
PROG
(Magma) [k:k in [1..650]| IsPrime( &+[a[s]^(a[s]): s in [1..# a]]) where a is Intseq(k) ]; // Marius A. Burtea, Sep 18 2019
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Patrick De Geest, Jul 15 1998
STATUS
approved