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A130536 Prime numbers arising from A057856. 2
3, 5, 7, 41, 11, 13, 113, 17, 19, 2211377674535255285545615254209921, 23, 313, 66977, 29, 31, 149057, 613, 37, 761, 41, 43, 1013, 47, 1201, 1301, 53, 1146097 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Conjecture: For all pairs of relative prime numbers (x, y) there exists at least one number n = 2^m and one prime number p such that p = x^n + y^n. This sequence shows one case of this conjecture where y = x + 1.

LINKS

Table of n, a(n) for n=1..27.

EXAMPLE

a(10)=2211377674535255285545615254209921 because A057856(10)=32 and 2211377674535255285545615254209921 = 10^32 + 11^32 = 100000000000000000000000000000000 + 2111377674535255285545615254209921.

PROG

(PARI) a(n) = my(k=1); while (!isprime(p=(n+1)^k + n^k), k++); p; \\ Michel Marcus, Sep 16 2018

CROSSREFS

Cf. A057856.

Sequence in context: A234569 A037287 A163797 * A261511 A146972 A102742

Adjacent sequences:  A130533 A130534 A130535 * A130537 A130538 A130539

KEYWORD

nonn,hard

AUTHOR

Tomas Xordan, Jun 02 2007

STATUS

approved

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Last modified September 23 16:17 EDT 2020. Contains 337314 sequences. (Running on oeis4.)