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 A186969 Smallest prime p such that k*p + k + 1 is prime for k=1..n. 0

%I

%S 3,5,5,4259,25409,25409,512819,512819,17733438029,1095010766849,

%T 766405913232959

%N Smallest prime p such that k*p + k + 1 is prime for k=1..n.

%e n=1: p=3 and p+2=5 both primes

%e n=2,3: p=5, p+2=7, 2*p+3=13, and 3*p+4=19 all four primes

%e n=4: p=4259, p+2=4261, 2*p+3=8521, 3*p+4=12781, and 4*p+5=17041 all five primes.

%K nonn,more,hard

%O 1,1

%A _Zak Seidov_, Mar 01 2011

%E a(10), a(11) from _Max Alekseyev_, Mar 10 2011

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Last modified December 9 04:13 EST 2022. Contains 358698 sequences. (Running on oeis4.)