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 A276203 Numbers k such that k^9 + 9^k is prime. 0
 2, 76, 122, 422, 2300, 5090, 7166, 58046, 91382, 234178, 314738 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Numbers k such that A185277(k) is prime. LINKS Hans Havermann, Indices of A094133 in A076980. Andrey V. Kulsha, Factorizations of x^y + y^x for 1 < y < x < 151. P. Leyland, Primes and Strong Pseudoprimes of the form x^y + y^x. EXAMPLE 2 is a term of the sequence, because A185277(2) = 593 is prime. PROG (PARI) is(n) = ispseudoprime(n^9+9^n) CROSSREFS Cf. A064539, A185277, A253471. Sequence in context: A282966 A351433 A351376 * A324216 A198704 A198623 Adjacent sequences: A276200 A276201 A276202 * A276204 A276205 A276206 KEYWORD nonn,hard,more AUTHOR Felix Fröhlich, Aug 27 2016 STATUS approved

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Last modified December 5 21:40 EST 2022. Contains 358594 sequences. (Running on oeis4.)