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A105451
Numbers k such that prime(k+1) == 8 (mod k).
7
1, 5, 15, 73, 75, 100347, 637329, 27067271, 179993015, 1208198523, 55762149023, 55762149103, 382465573515
OFFSET
1,2
COMMENTS
No additional terms up to 7 million. - Harvey P. Dale, Jan 23 2012
Integers k such that A004649(k+1) = 8. - Michel Marcus, Dec 30 2022
MATHEMATICA
bb={}; Do[If[8==Mod[Prime[n+1], n], bb=Append[bb, n]], {n, 1, 1000000}]; bb
Select[Range[700000], Mod[Prime[#+1], #]==8&] (* Harvey P. Dale, Jan 23 2012 *)
PROG
(Python)
from sympy import nextprime
def A105451(max):
terms = []
p = 3
for n in range(1, max+1):
if (p - 8) % n == 0: terms.append(n)
p = nextprime(p)
return terms
# Eric M. Schmidt, Feb 05 2013
CROSSREFS
Cf. A023150 (Numbers k such that prime(n) == 8 (mod k)).
Sequence in context: A149650 A318376 A186364 * A149651 A149652 A151487
KEYWORD
nonn,more
AUTHOR
Zak Seidov, May 02 2005
EXTENSIONS
First two terms inserted by Eric M. Schmidt, Feb 05 2013
a(8)-a(10) from Michel Marcus, Dec 29 2022
a(11)-a(13) from Max Alekseyev, Aug 31 2024
STATUS
approved