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A057936
Number of prime factors of 8^n + 1 (counted with multiplicity).
16
2, 2, 4, 2, 4, 4, 4, 3, 6, 6, 5, 4, 4, 6, 7, 3, 6, 6, 5, 4, 7, 6, 5, 5, 7, 10, 10, 5, 5, 11, 5, 3, 9, 9, 11, 6, 7, 8, 7, 6, 7, 10, 6, 7, 12, 8, 7, 7, 7, 14, 11, 5, 6, 10, 12, 8, 9, 8, 8, 8, 4, 9, 13, 4, 11, 12, 8, 9, 8, 15, 8, 8, 6, 10, 12, 8, 12, 17, 6, 7, 15, 10, 9, 12, 12, 10, 11, 8, 8, 18, 12
OFFSET
1,1
LINKS
Max Alekseyev, Table of n, a(n) for n = 1..502 (first 354 terms from Amiram Eldar)
S. S. Wagstaff, Jr., The Cunningham Project
FORMULA
a(n) = A057953(2n) - A057953(n). - T. D. Noe, Jun 19 2003
a(n) = A001222(A062395(n)) = A054992(3*n). - Amiram Eldar, Feb 02 2020
MATHEMATICA
PrimeOmega[8^Range[100]+1] (* Harvey P. Dale, Dec 16 2014 *)
PROG
(Magma) f:=func<n|&+[p[2]: p in Factorization(n)]>; [f(8^n + 1):n in [1..110]]; // Marius A. Burtea, Feb 02 2020
CROSSREFS
bigomega(b^n+1): A057934 (b=10), A057935 (b=9), this sequence (b=8), A057937 (b=7), A057938 (b=6), A057939 (b=5), A057940 (b=4), A057941 (b=3), A054992 (b=2).
Sequence in context: A100008 A102763 A054844 * A033097 A036845 A094269
KEYWORD
nonn
AUTHOR
Patrick De Geest, Oct 15 2000
STATUS
approved