A377540 Numbers k such that at least one of the numbers 6k-1 or 6k+1 is prime

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 25, 26, 27, 28, 29, 30, 32, 33, 35, 37, 38, 39, 40, 42, 43, 44, 45, 46, 47, 49, 51, 52, 53, 55, 56, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 70, 72, 73, 74, 75, 76, 77, 78, 80, 81, 82, 83, 84, 85, 87

Offset

1,2

Links

Table of n, a(n) for n=1..73.

Mathematica

Select[Range[100], PrimeQ[6 # - 1] || PrimeQ[6 # + 1] &]

Prog

(PARI) isok(k) = isprime(6*k-1) || isprime(6*k+1); \\ Michel Marcus, Oct 31 2024

Crossrefs

Union of A024898 and A024899.

Cf. A002476, A007528.

Complement of A060461 (with respect to the positive integers) or A171696 (with respect to the nonnegative integers).

Sequence in context: A346132 A320249 A309066 * A084981 A326880 A359077

Adjacent sequences: A377537 A377538 A377539 * A377541 A377542 A377543

Keyword

nonn,easy

Author

Michel Eduardo Beleza Yamagishi, Oct 31 2024

Status

approved