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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
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
Sequence in context: A213450 A099809 A271588 * A145214 A172662 A201303
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 April 22 18:29 EDT 2024. Contains 371906 sequences. (Running on oeis4.)