A045963 - OEIS

%I #22 Mar 20 2024 05:15:08

%S 2,4,6,10,12,22,34,36,42,52,54,70,76,84,90,100,114,132,234,244,246,

%T 262,282,300,310,324,346,372,394,406,420,442,474,516,532,546,586,630,

%U 642,646,660,684,714,724,742,772,780,790,804,874,906,916,954,966,994,1002,1044

%N Numbers k in A045954 such that 2*k-1 is prime.

%H Amiram Eldar, <a href="/A045963/b045963.txt">Table of n, a(n) for n = 1..10000</a>

%t seq[max_] := Module[{lst = Range[2, max, 2], i = 2, len}, While[i <= (len = Length@lst) && (k = lst[[i]]) <= len, lst = Drop[lst, {k, len, k}]; i++]; Select[lst, PrimeQ[2*# - 1] &]]; seq[1000] (* _Amiram Eldar_, Mar 20 2024, after _Robert G. Wilson v_ at A045954 *)

%Y Cf. A045954, A045962.

%Y Subsequence of A006254.

%K nonn

%O 1,1

%A _Felice Russo_

%E More terms from _David W. Wilson_

%E Title corrected by _Sean A. Irvine_, Mar 29 2021