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A339182 Primes p such that q = p mod A001414(p-1) = p mod A001414(p+1) is prime. 2
251, 991, 1429, 1567, 1597, 1741, 2243, 3739, 4003, 4049, 4129, 4271, 4513, 5407, 6673, 6733, 9539, 9631, 10639, 14627, 14947, 16561, 18617, 18749, 18797, 19081, 20551, 24851, 28729, 31151, 37571, 42641, 49529, 50047, 54751, 56897, 59513, 65563, 73751, 75683, 77743, 89783, 91807, 96799, 104537 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Members p of A339180 such that p mod A001414(p-1) is prime.

LINKS

Robert Israel, Table of n, a(n) for n = 1..2300

EXAMPLE

a(4) = 1567 is in the sequence because 1567 is prime, A001414(1566) = 2+3+3+3+29 = 40, A001414(1568) = 2+2+2+2+2+7+7=24, 1567 mod 40 = 1567 mod 24 = 7 is prime.

MAPLE

spf:= n -> add(t[1]*t[2], t=ifactors(n)[2]):

filter:= proc(p) local v;

if not isprime(p) then return false fi;

v:= p mod spf(p-1);

isprime(v) and p mod spf(p+1) = v

end proc:

select(filter, [seq(i, i=3..10^5, 2)]);

CROSSREFS

Cf. A001414, A339180.

Sequence in context: A179231 A108833 A228672 * A008917 A025396 A185941

Adjacent sequences:  A339179 A339180 A339181 * A339183 A339184 A339185

KEYWORD

nonn

AUTHOR

J. M. Bergot and Robert Israel, Nov 26 2020

STATUS

approved

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Last modified June 17 05:45 EDT 2021. Contains 345080 sequences. (Running on oeis4.)