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Numbers m such that prime(m) = pi(m)*k + 1 for some k.
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%I #8 Mar 04 2022 11:14:56

%S 3,4,6,7,10,11,14,21,37,45,47,53,55,63,75,81,101,115,121,125,136,183,

%T 209,230,271,313,319,327,348,377,399,425,460,575,581,738,786,792,850,

%U 881,917,1076,1110,1152,1246,1519,1740,2062,2074,2119,2144,2327,2361

%N Numbers m such that prime(m) = pi(m)*k + 1 for some k.

%F Solutions to Mod[A000040(x), A000720(x)]=1.

%F Values satisfying A065133(x)=1.

%e x=581 is a term because prime(581) = 4211 = 106*40 + 1 = 40*pi(581) + 1.

%o (PARI) isok(m) = if (m>1, prime(m) % primepi(m) == 1); \\ _Michel Marcus_, Mar 04 2022

%Y Cf. A000040, A000720, A065133.

%K nonn

%O 1,1

%A _Labos Elemer_, Oct 15 2001