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A366636
Number of distinct prime divisors of 7^n + 1.
9
1, 1, 2, 2, 2, 3, 4, 3, 3, 3, 4, 3, 5, 3, 3, 5, 3, 2, 5, 3, 4, 6, 5, 2, 4, 4, 4, 4, 6, 2, 8, 4, 4, 6, 5, 9, 8, 3, 3, 7, 6, 5, 6, 8, 5, 10, 6, 2, 6, 10, 8, 6, 5, 5, 8, 10, 8, 7, 6, 5, 9, 2, 5, 12, 4, 7, 11, 4, 5, 6, 8, 3, 9, 4, 3, 9, 7, 10, 8, 5, 6, 8, 5, 3, 12
OFFSET
0,3
LINKS
FORMULA
a(n) = omega(7^n+1) = A001221(A034491(n)).
MATHEMATICA
PrimeNu[7^Range[0, 84] + 1] (* Paul F. Marrero Romero, Nov 11 2023 *)
PROG
(PARI) for(n = 0, 100, print1(omega(7^n + 1), ", "))
KEYWORD
nonn
AUTHOR
Sean A. Irvine, Oct 15 2023
STATUS
approved