A237190 Numbers k such that k+1, 2k+1, 3k+1, 4k+1, 5k+1 are five primes.

10830, 25410, 26040, 88740, 165900, 196560, 211050, 224400, 230280, 247710, 268500, 268920, 375480, 377490, 420330, 451410, 494340, 512820, 592620, 604170, 735750, 751290, 765780, 799170, 808080, 952680, 975660, 1053690, 1064190, 1132860, 1156170, 1532370, 1559580

Offset

1,1

Comments

A subsequence of A237189.

All terms are divisible by 30, and b(n) = a(n)/30 begins: 361, 847, 868, 2958, 5530, 6552, 7035, 7480, 7676, 8257, 8950, 8964, 12516, 12583, 14011, ...

Links

Giovanni Resta, Table of n, a(n) for n = 1..1000

Mathematica

Select[30*Range[52000], AllTrue[#*Range[5]+1, PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Dec 31 2017 *)

Prog

(Python)
from sympy import isprime
for n in range(2000000):
    if isprime(n+1) and isprime(2*n+1) and isprime(3*n+1) and isprime(4*n+1) and isprime(5*n+1):
        print(n, end=', ')

Crossrefs

Cf. A088250, A064238, A124410, A237189.

Sequence in context: A144716 A123078 A235254 * A065321 A252064 A295993

Adjacent sequences: A237187 A237188 A237189 * A237191 A237192 A237193

Keyword

nonn

Author

Alex Ratushnyak, Feb 04 2014

Status

approved