A273088 a(n) is a multiple of 6 and a(n)-1 or a(n)+1 is an isolated (non-twin) prime number.

24, 36, 48, 54, 66, 78, 84, 90, 96, 114, 126, 132, 156, 162, 168, 174, 210, 222, 234, 252, 258, 264, 276, 294, 306, 318, 330, 336, 354, 360, 366, 372, 378, 384, 390, 396, 402, 408, 438, 444, 450, 456, 468, 480, 486, 492, 498, 504, 510, 540, 546, 558, 564, 576, 588, 594

Offset: 1

Author

Dimitris Valianatos, May 14 2016

Keywords

• nonn

Examples

			66=6*11 and 66+1=67 are not twin primes, so 66 is a term.
		

Links

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

Crossrefs

Intersection of A008588 and A100317.

Programs

Maple

select(t -> isprime(t-1) <> isprime(t+1), 6*[$1..200]);  # Robert Israel, Jul 10 2023

Mathematica

Select[6 Range@ 100, Total@ Boole@ Map[If[PrimeQ@ #, Count[Abs[# - {NextPrime[#, -1], NextPrime@ #}], k_ /; k == 2] < 1, False] &, {# - 1, # + 1}] > 0 &] (* Michael De Vlieger, May 15 2016 *)

PARI

{
  forstep(n=6,1000,6,
    if((isprime(n-1)+isprime(n+1))==1,
      print1(n", ")
    )
  )
}