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A116658
Numbers k such that prime(k) == 13 (mod k).
5
1, 2, 6, 12, 22, 40, 42, 84, 86, 90, 193, 2712, 16056, 16058, 40077, 40123, 40124, 40125, 251720, 251766, 251769, 251787, 637332, 10553432, 10553435, 10553501, 10553568, 10553817, 10553826, 27067042, 27067132, 69709722, 179993160, 465769803
OFFSET
1,2
COMMENTS
Starting with a(5), positions of 13 in A004648. - corrected by Eric M. Schmidt, Feb 05 2013
MATHEMATICA
NextPrim[n_] := Block[{k = n + 1}, While[ !PrimeQ[k], k++ ]; k]; p = 1; Do[ If[ Mod[p = NextPrim[p], n] == 13, Print[n]], {n, 10^9}] (* Robert G. Wilson v, Feb 22 2006 *)
PROG
(Sage)
def A116658(max) :
terms = []
p = 2
for n in range(1, max+1) :
if (p - 13) % n == 0 : terms.append(n)
p = next_prime(p)
return terms
# Eric M. Schmidt, Feb 05 2013
CROSSREFS
Cf. A004648; A023143 - A023152, A116657, A116677, A116658, A116659: prime(n) == m (mod n), m=1..14.
Sequence in context: A304627 A168193 A182977 * A210065 A208850 A131520
KEYWORD
nonn
AUTHOR
Zak Seidov, Feb 21 2006
EXTENSIONS
a(24)-a(34) from Robert G. Wilson v, Feb 22 2006
First four terms inserted by Eric M. Schmidt, Feb 05 2013
STATUS
approved