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A103871
Numbers n such that 100n + 69 is prime.
1
2, 5, 7, 10, 16, 20, 22, 29, 31, 34, 37, 49, 55, 56, 58, 62, 64, 65, 68, 70, 73, 76, 80, 82, 83, 86, 89, 97, 100, 101, 103, 110, 113, 119, 122, 125, 134, 136, 143, 146, 148, 149, 152, 155, 160, 163, 175, 176, 181, 182, 188, 190, 194, 202, 203, 211, 212, 215, 223
OFFSET
1,1
LINKS
FORMULA
a(n) ~ 0.4n log n.
EXAMPLE
n=2: 269 is prime.
n=49: 4969 is prime.
n=97: 9769 is prime.
MAPLE
filter:= proc(n) isprime(100*n+69) end proc:
select(filter, [$1..300]); # Robert Israel, Sep 30 2018
PROG
(Magma) [ n: n in [1..300] | IsPrime(Seqint([9, 6] cat Intseq(n))) ];
(PARI) is(n)=isprime(100*n+69) \\ Charles R Greathouse IV, Jun 13 2017
CROSSREFS
Sequence in context: A102339 A172410 A266594 * A068817 A156779 A345127
KEYWORD
nonn,easy
AUTHOR
Parthasarathy Nambi, Mar 30 2005
STATUS
approved