A105451 - OEIS

%I #29 Sep 17 2024 16:03:33

%S 1,5,15,73,75,100347,637329,27067271,179993015,1208198523,55762149023,

%T 55762149103,382465573515

%N Numbers k such that prime(k+1) == 8 (mod k).

%C No additional terms up to 7 million. - _Harvey P. Dale_, Jan 23 2012

%C Integers k such that A004649(k+1) = 8. - _Michel Marcus_, Dec 30 2022

%t bb={};Do[If[8==Mod[Prime[n+1], n], bb=Append[bb, n]], {n, 1, 1000000}];bb

%t Select[Range[700000],Mod[Prime[#+1],#]==8&] (* _Harvey P. Dale_, Jan 23 2012 *)

%o (Python)

%o from sympy import nextprime

%o def A105451(max):

%o     terms = []

%o     p = 3

%o     for n in range(1, max+1):

%o         if (p - 8) % n == 0: terms.append(n)

%o         p = nextprime(p)

%o     return terms

%o # Eric M. Schmidt, Feb 05 2013

%Y Cf. A004649, A105286, A105287, A105288, A105290, A105329.

%Y Cf. A023150 (Numbers k such that prime(n) == 8 (mod k)).

%K nonn,more

%O 1,2

%A _Zak Seidov_, May 02 2005

%E First two terms inserted by _Eric M. Schmidt_, Feb 05 2013

%E a(8)-a(10) from _Michel Marcus_, Dec 29 2022

%E a(11)-a(13) from _Max Alekseyev_, Aug 31 2024