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A186969
Smallest prime p such that k*p + k + 1 is prime for k=1..n.
0
3, 5, 5, 4259, 25409, 25409, 512819, 512819, 17733438029, 1095010766849, 766405913232959
OFFSET
1,1
EXAMPLE
n=1: p=3 and p+2=5 both primes
n=2,3: p=5, p+2=7, 2*p+3=13, and 3*p+4=19 all four primes
n=4: p=4259, p+2=4261, 2*p+3=8521, 3*p+4=12781, and 4*p+5=17041 all five primes.
CROSSREFS
Sequence in context: A320433 A165142 A231809 * A111950 A274792 A243589
KEYWORD
nonn,more,hard
AUTHOR
Zak Seidov, Mar 01 2011
EXTENSIONS
a(10), a(11) from Max Alekseyev, Mar 10 2011
STATUS
approved