OFFSET
1,3
COMMENTS
FORMULA
EXAMPLE
From Daniel Suteu, Mar 29 2021: (Start)
For a(3), as A003618(1) = 7, A003618(2) = 97 and A003618(3) = 997, we have A342834(3) = 7||97||997 = 797997 while prime A338968(3) = 7||97||977 = 797977.
# 7||97||997 = 797997 = 3 * 17 * 15647 is not prime (#1 fail)
# 7||97||991 = 797991 = 3 * 461 * 577 is not prime (#2 fail)
# 7||97||983 = 797983 = 41 * 19463 is not prime (#3 fail)
# 7||97||977 = 797977 = A338968(3) is prime.
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Bernard Schott, Mar 29 2021
EXTENSIONS
a(3)-a(57) from Daniel Suteu, Mar 29 2021
STATUS
approved