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A229570
Primes of form p*q + 30, where p and q are consecutive primes.
1
107, 173, 251, 353, 467, 929, 2521, 4787, 7417, 8663, 10433, 12347, 17977, 19073, 25621, 28921, 32429, 39233, 42019, 50651, 55717, 60521, 77867, 95507, 97373, 99251, 111577, 116969, 126757, 131783, 141397, 159227, 164039, 171401, 186653, 194507, 198937, 205223
OFFSET
1,1
COMMENTS
Conjecture: The expression p*q + c with p and q consecutive primes and c = 30 generates more primes than any other value of c in the range 1 < c < 100 and p = 48611 which is 5000th prime. Hence, c = 30 is considered for this sequence.
LINKS
EXAMPLE
a(1)=107: prime(4)*prime(5)+30=107, which is prime.
a(6)=929: prime(10)*prime(11)+30=929, which is prime.
MAPLE
KD:= proc() local a; a:= ithprime(n)*ithprime(n+1)+30; if isprime((a)) then RETURN((a)):fi; end: seq(KD(), n=1..500);
MATHEMATICA
Select[Table[Prime[n]*Prime[n+1]+30, {n, 100}], PrimeQ]
CROSSREFS
Cf. A048880.
Sequence in context: A142662 A178416 A182477 * A107215 A142142 A265915
KEYWORD
nonn
AUTHOR
K. D. Bajpai, Sep 26 2013
STATUS
approved