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A057938
Number of prime factors of 6^n + 1 (counted with multiplicity).
14
1, 1, 2, 1, 3, 3, 4, 2, 3, 3, 2, 2, 4, 3, 5, 3, 3, 6, 3, 3, 6, 4, 3, 4, 4, 4, 5, 5, 4, 9, 2, 3, 6, 3, 11, 5, 4, 3, 9, 5, 4, 7, 2, 3, 7, 5, 2, 7, 7, 6, 8, 4, 5, 10, 8, 6, 7, 3, 2, 6, 3, 2, 10, 3, 8, 11, 5, 5, 6, 7, 4, 5, 6, 5, 10, 5, 6, 11, 6, 6, 8, 4, 5, 8, 8, 5, 11, 4, 3, 16, 12, 4, 5, 5, 10, 4, 4, 5
OFFSET
1,3
LINKS
Max Alekseyev, Table of n, a(n) for n = 1..420 (first 408 terms from Amiram Eldar)
S. S. Wagstaff, Jr., The Cunningham Project
FORMULA
a(n) = A057955(2n) - A057955(n). - T. D. Noe, Jun 19 2003
a(n) = A001222(A062394(n)). - Amiram Eldar, Feb 02 2020
MATHEMATICA
PrimeOmega[6^Range[100]+1] (* Harvey P. Dale, Mar 10 2013 *)
PROG
(Magma) f:=func<n|&+[p[2]: p in Factorization(n)]>; [f(6^n + 1):n in [1..100]]; // Marius A. Burtea, Feb 02 2020
CROSSREFS
bigomega(b^n+1): A057934 (b=10), A057935 (b=9), A057936 (b=8), A057937 (b=7), this sequence (b=6), A057939 (b=5), A057940 (b=4), A057941 (b=3), A054992 (b=2).
Sequence in context: A082666 A363619 A363625 * A375729 A144623 A340284
KEYWORD
nonn
AUTHOR
Patrick De Geest, Oct 15 2000
STATUS
approved