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A344424 Numbers k such that A344423(k) is prime. 1
3, 54, 58, 64, 70, 253, 438, 4255, 8770 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(10) > 10000. - Hugo Pfoertner, May 19 2021

LINKS

Table of n, a(n) for n=1..9.

EXAMPLE

A344423(3) = 100111001 is prime, so 3 is a term of the sequence.

PROG

(PARI) is(n) = ispseudoprime(10^(2*n+2) + 111*10^n + 1)

CROSSREFS

Cf. A070247, A100580, A344423.

Sequence in context: A208631 A093164 A092448 * A045481 A275566 A068380

Adjacent sequences:  A344421 A344422 A344423 * A344425 A344426 A344427

KEYWORD

nonn,hard,more

AUTHOR

Felix Fröhlich, May 18 2021

EXTENSIONS

a(9) from Hugo Pfoertner, May 19 2021

STATUS

approved

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Last modified August 1 13:17 EDT 2021. Contains 346391 sequences. (Running on oeis4.)