A158021 Primes such that p, 10*p-1 and (p-1)/2 are all prime.

11, 23, 83, 107, 167, 179, 227, 347, 479, 587, 839, 863, 983, 1283, 1367, 1439, 1487, 1619, 1823, 1907, 2027, 2039, 2447, 2879, 2963, 2999, 3119, 3203, 3623, 3863, 4127, 4139, 4259, 4283, 4787, 5099, 5483, 5879, 6719, 6779, 6983, 7247, 7703, 7727, 7823

Offset

1,1

Links

Robert Israel, Table of n, a(n) for n = 1..10000

Maple

filter:= proc(n) isprime(n) and isprime((n-1)/2) and isprime(10*n-1) end proc:
select(filter, [seq(i, i=3 .. 10000, 4)]); # Robert Israel, Dec 12 2024

Mathematica

Flatten[Table[If[PrimeQ[n] && PrimeQ[10*n - 1] && PrimeQ[( n - 1)/2], n, {}], {n, 1, 10000}]]

Crossrefs

Cf. A059455. Intersection of A000040 and A158019.

Sequence in context: A184394 A060160 A241973 * A239638 A050767 A145918

Adjacent sequences: A158018 A158019 A158020 * A158022 A158023 A158024

Keyword

nonn

Author

Roger L. Bagula and Gary W. Adamson, Mar 11 2009

Status

approved