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A355307
Carmichael numbers ending in 7.
5
46657, 126217, 748657, 1569457, 4909177, 9613297, 11972017, 40160737, 55462177, 65037817, 106041937, 161035057, 178451857, 193910977, 196358977, 311388337, 328573477, 338740417, 358940737, 403043257, 461502097, 499310197, 556450777, 569332177, 633639097, 784966297, 902645857, 981789337, 1125038377
OFFSET
1,1
MATHEMATICA
Select[10*Range[0, 10^7] + 7, CompositeQ[#] && Divisible[# - 1, CarmichaelLambda[#]] &] (* Amiram Eldar, Jul 24 2022 *)
PROG
(Python)
from itertools import count, islice
from sympy import factorint
def A355307_gen(): # generator of terms
for n in count(7, 10):
f = factorint(n)
if len(f) == sum(f.values()) > 1 and not any((n-1) % (p-1) for p in f):
yield n
A355307_list = list(islice(A355307_gen(), 5)) # Chai Wah Wu, Jul 25 2022
CROSSREFS
Intersection of A002997 and A017353.
Sequence in context: A223362 A143163 A132642 * A265285 A255514 A251502
KEYWORD
nonn,base
AUTHOR
Omar E. Pol, Jul 24 2022
STATUS
approved