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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..11.

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

Adjacent sequences:  A186966 A186967 A186968 * A186970 A186971 A186972

KEYWORD

nonn,more,hard

AUTHOR

Zak Seidov, Mar 01 2011

EXTENSIONS

a(10), a(11) from Max Alekseyev, Mar 10 2011

STATUS

approved

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Last modified April 18 03:59 EDT 2021. Contains 343072 sequences. (Running on oeis4.)