A351875 - OEIS

%I #7 Feb 25 2022 19:36:14

%S 1,2,6,18,30,36,78,96,138,156,198,210,228,270,306,330,336,366,378,438,

%T 498,546,576,600,606,618,660,690,726,810,828,876,936,966,996,1008,

%U 1068,1170,1236,1278,1296,1398,1428,1458,1530,1608,1626,1656,1758,1866,2010,2028,2088,2130

%N Positive difference of the distinct prime factors of A129521(n).

%F a(n) = A005383(n) - A005382(n).

%F a(n) = A005382(n) - 1. - _Amiram Eldar_, Feb 23 2022

%e a(4) = 18; A005383(4) - A005382(4) = 37 - 19 = 18.

%t Select[Prime[Range[350]], PrimeQ[2*# - 1] &] - 1 (* _Amiram Eldar_, Feb 23 2022 *)

%Y Cf. A005382, A005383, A129521.

%K nonn

%O 1,2

%A _Wesley Ivan Hurt_, Feb 22 2022