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%I #20 Feb 20 2023 10:01:59
%S 1,2,3,4,5,6,10,12,14,70,72,181,182,440,1053,6458,6459,6460,6461,6466,
%T 6471,40087,40089,100362,251712,251732,251737,251742,637236,637320,
%U 637334,637336,1617173,4124466,10553445,10553455,10553504,10553505,10553547,10553569
%N Numbers k that divide prime(k)+1 or prime(k)-1.
%F Equals A023143 union A045924.
%F a(n) = A000720(A162567(n)). - _Alois P. Heinz_, Feb 20 2023
%e 181 is in the sequence because the 181st prime is 1087, and 1086 is divisible by 181 (although 1088 is not so divisible).
%t ndpQ[n_]:=Module[{p=Prime[n]},Divisible[p-1,n]||Divisible[p+1,n]]; Select[Range[100000],ndpQ] (* _Harvey P. Dale_, Apr 03 2011 *)
%Y Cf. A000720, A162567.
%K nonn
%O 1,2
%A _Benoit Cloitre_, Jan 12 2003
%E Corrected and example added by _Harvey P. Dale_, Apr 03 2011
%E Extended with terms from A023143 and A045924 by _Michel Marcus_, Nov 30 2013
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