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A233464 a(n) is the smallest natural number m such that 10^10^k + m is prime for k = 0, 1, ...., n. 0
1, 19, 5641, 1289743, 2578966671 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..4.

EXAMPLE

29 (=10^1+19) and 10000000019 (=10^10+19) are primes so a(1)=19.

PROG

(PARI) okm(m, n) = {for (k=0, n, if (!isprime(10^10^k + m), return (0)); ); return (1); }

a(n) = {m = 0; while (!okm(m, n), m++); m; } \\ Michel Marcus, Mar 16 2014

CROSSREFS

Cf. A129613, A129614, A129615.

Sequence in context: A213450 A099809 A271588 * A145214 A172662 A201303

Adjacent sequences: A233461 A233462 A233463 * A233465 A233466 A233467

KEYWORD

nonn,hard,more

AUTHOR

Farideh Firoozbakht, Mar 13 2014

EXTENSIONS

a(4) from Giovanni Resta, Mar 14 2014

STATUS

approved

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Last modified December 7 12:12 EST 2022. Contains 358656 sequences. (Running on oeis4.)